All Exams  >   Class 10  >   Olympiad Preparation for Class 10  >   All Questions

All questions of Polynomials for Class 10 Exam

If the sum of squares of zeros of the quadratic polynomial P(x) = x2 - 8x + k is 40. What is the value of k?
  • a)
    12
  • b)
    16
  • c)
    18
  • d)
    8
Correct answer is option 'A'. Can you explain this answer?

Ritu Saxena answered
P(x) = x2 - 8x + k
If α, and β are its zeros
then α + β = 8, αβ = k
and α2 + β2 = 40
⇒ (α + β)2 - 2αβ = 82 - 2k
⇒ 40 = 64 - 2k
⇒ 2k = 24
⇒ k = 12

What must be added to f (x) = 4 x 4 +2x3− 2 x 2 +x−1 so that the resulting polynomial is divisible by g (x) = x 2 + 2x −3 ?
  • a)
    61x - 65
  • b)
    -61x + 65
  • c)
    -61x - 65
  • d)
    None of these
Correct answer is option 'B'. Can you explain this answer?

Anmol tiwari answered
Explanation:

Step 1: Find the quotient when f(x) is divided by g(x)
- To find the quotient, divide f(x) by g(x) using polynomial division.
- Quotient = 4x^2 - 6x + 9

Step 2: Multiply the quotient by g(x) to get the product polynomial
- Multiply the quotient (4x^2 - 6x + 9) by g(x) (x^2 + 2x - 3) to get the product polynomial.
- Product polynomial = 4x^4 - 6x^3 + 9x^2 + 8x^3 - 12x^2 + 18x - 12x^2 + 18x - 27
- Product polynomial = 4x^4 + 2x^3 - 2x^2 + 27

Step 3: Find the difference between the product polynomial and f(x)
- Subtract f(x) from the product polynomial to find the difference.
- Difference = 4x^4 + 2x^3 - 2x^2 + 27 - (4x^4 + 2x^3 - 2x^2 + x - 1)
- Difference = 4x^4 + 2x^3 - 2x^2 + 27 - 4x^4 - 2x^3 + 2x^2 - x + 1
- Difference = -x + 28

Step 4: Determine the polynomial to add to f(x) to make it divisible by g(x)
- The polynomial that needs to be added to f(x) is the difference (-x + 28).
- This can be simplified to -x + 28 = -1x + 28 = -x + 28
Therefore, the polynomial that must be added to f(x) = 4x^4 + 2x^3 - 2x^2 + x - 1 is -x + 28 to make the resulting polynomial divisible by g(x) = x^2 + 2x - 3.
Thus, the correct answer is option -61x + 65.

If a , b are zeros of 2x2 +5x−10 then what is the value of αβ?
  • a)
    -5
  • b)
    5
  • c)
  • d)
Correct answer is option 'A'. Can you explain this answer?

There seems to be a typo in the question, as 2x2 5x is not a valid polynomial expression. Please provide the correct expression so that we can help you solve the problem.

Find a cubic polynomial whose roots are -2, -3, and -1.
  • a)
    x3 − 6x2+9 x + 6
  • b)
    x3 + 6x2+11x +6
  • c)
    x3 + 6x2−11x −6
  • d)
    None of these
Correct answer is option 'B'. Can you explain this answer?

Ritu Saxena answered
We have α + β+ y = -2 - 3 - 1 = -6 αβ + βy + yα
= (-2) (-3) + (-3) (-1) +(-1) (-2) = 6 + 3 + 2 = 11
and αβγ = (-2) (-3) (-1) = -6
∴ Required polynomial
= x3 - (-6)x2 + 11x - (-6)
= x3 + 6x2 + 11x + 6

For x2 + 2x + 5 to be a factor of x4 + αx2 + β, the values of α and β should respectively be _______.
  • a)
    2, 5
  • b)
    5, 25
  • c)
    6, 25
  • d)
    5, 2
Correct answer is option 'C'. Can you explain this answer?

Priya shah answered
To determine if x^2 + 2x + 5 is a factor of x^4 + ax^3 + bx^2 + cx + d, we need to perform polynomial division.

The division would look like this:

_____________________
x^2 + 2x + 5 | x^4 + ax^3 + bx^2 + cx + d

We start by dividing the first term of the dividend (x^4) by the first term of the divisor (x^2), which gives us x^2. We then multiply x^2 by the divisor (x^2 + 2x + 5), which gives us x^4 + 2x^3 + 5x^2.

Next, we subtract this product from the dividend:

x^4 + ax^3 + bx^2 + cx + d - (x^4 + 2x^3 + 5x^2)

This simplifies to:

ax^3 + (b - 2)x^2 + cx + d - 5x^2

We repeat the process by dividing the first term of the remaining expression (ax^3) by the first term of the divisor (x^2), which gives us a/x. We then multiply a/x by the divisor (x^2 + 2x + 5), which gives us a + 2ax + 5(a/x).

Next, we subtract this product from the remaining expression:

ax^3 + (b - 2)x^2 + cx + d - (a + 2ax + 5(a/x))

This simplifies to:

(b - 2 - 2a)x^2 + (c - 5(a/x))x + (d - 5a)

We repeat this process until we reach the end of the dividend.

For x^2 + 2x + 5 to be a factor, the remainder at the end of the division should be zero. In other words, we need the expression (b - 2 - 2a)x^2 + (c - 5(a/x))x + (d - 5a) to be equal to zero.

Therefore, for x^2 + 2x + 5 to be a factor of x^4 + ax^3 + bx^2 + cx + d, the coefficients (b - 2 - 2a), (c - 5(a/x)), and (d - 5a) must all equal zero.

If one zero of the polynomial f (x) = (k2 + 4) x2 + 13x + 4k is reciprocal of the other, then k is equal to _______.
  • a)
    2
  • b)
    –2
  • c)
    1
  • d)
    –1
Correct answer is option 'A'. Can you explain this answer?

Anirban Yadav answered
Understanding the problem:
One zero of the polynomial f(x) = (k^2 + 4)x^2 + 13x + 4k is the reciprocal of the other zero. We need to find the value of k that satisfies this condition.

Key Concept:
If α and β are the zeros of a quadratic polynomial ax^2 + bx + c, then αβ = c/a and α + β = -b/a.

Solution:
Let the zeros of the polynomial f(x) be α and 1/α where α ≠ 0.
Using the sum of zeros formula:
α + 1/α = -13/(k^2 + 4) ...(1)
Using the product of zeros formula:
α * (1/α) = 4k/(k^2 + 4) = 1
4k = k^2 + 4
k^2 - 4k + 4 = 0
(k - 2)^2 = 0
k = 2
Therefore, k = 2 satisfies the condition that one zero of the polynomial is the reciprocal of the other.
Therefore, the correct answer is option 'A' (2).

Area of a triangular field is (x4 – 6x3 – 26x2 + 138x – 35) m2 and base of the triangular field is (x2 – 4x + 1) m. Find the height of the triangular field.
  • a)
    2(x2 – 2x – 35) m
  • b)
    1/2(x2 − 2x−35) m
  • c)
    2(3x2 – x – 4) m
  • d)
    1/2(3x2 −x−4) m
Correct answer is option 'A'. Can you explain this answer?

Ritu Saxena answered
Base of the triangular field = (x2 – 4x + 1) m
Area of the triangular field = (1/2) x Base x Height
Now, x4 – 6x3 – 26x2 + 138x – 35 = 1/2 x (x2 − 4x + 1) × Height
⇒ Height = 

∴ Height = 2(x2 – 2x – 35) m

Two different container contains (2x3 + 2x2 + 3x + 3) L and (4x3 – 2x2 + 6x – 3)L water. What is biggest measure that can measure both quantities exactly?
  • a)
    (x2 + 2x) L
  • b)
    (2x2 + 3) L
  • c)
    (2x – 1) L
  • d)
    (x + 1)  L
Correct answer is option 'B'. Can you explain this answer?

Vivek Bansal answered
Capacity of both the containers is (2x3 + 2x2 + 3x + 3) L and (4x3 – 2x2 + 6x – 3) L
i.e., (2x2 + 3)(x + 1) L and (2x2 + 3)(2x – 1) L
Required measure is the H.C.F. of capacity of both the containers i.e., (2x2 + 3) L

Which quadratic polynomial has sum of whose zeros is -5 and product of its zero is -12?
  • a)
    x 2 + 5x − 12
  • b)
    x2 - 5x + 12
  • c)
    x2 − 5x + 6
  • d)
    x2 −10x + 12
Correct answer is option 'A'. Can you explain this answer?

Malini sharma answered
Sum and Product of Zeros
- The sum of the zeros of a quadratic polynomial is given by the formula:
- Sum of zeros = -b/a
- The product of the zeros of a quadratic polynomial is given by the formula:
- Product of zeros = c/a

Given Information
- Sum of zeros = -5
- Product of zeros = -12

Solving for the Quadratic Polynomial
- Let the quadratic polynomial be ax^2 + bx + c
- Using the given information, we have:
- -b/a = -5
- c/a = -12

Equations to Solve
1. -b/a = -5
2. c/a = -12

Solving the Equations
- From equation 1, we get: b = 5a
- Substituting b = 5a into equation 2, we get: c/a = -12
- Solving for c, we get: c = -12a

Forming the Quadratic Polynomial
- The quadratic polynomial becomes: ax^2 + 5ax - 12a

Final Quadratic Polynomial
- Factoring out an 'a', we get: a(x^2 + 5x - 12)
- Therefore, the quadratic polynomial is: x^2 + 5x - 12, which corresponds to option 'A'.

If a and b are the roots of the quadratic equation x2 + px + 12 = 0 with the condition a – b = 1, then the value of ‘p’ is _______.
  • a)
    1
  • b)
    7
  • c)
    –7
  • d)
    7 or –7
Correct answer is option 'D'. Can you explain this answer?

Given equation is x2 + px + 12 = 0
Now, if a and b are its roots, then sum of roots, a + b = –p and product of roots, a × b = 12
Also, a – b = 1 (Given)
We know that, (a – b)2 = (a + b)2 – 4ab
⇒ 1 = p2 – 4 × 12 ⇒ 1 = p2 – 48 ⇒ p2 = 49 ⇒ p = ±7

Raghav had ₹(6x3 + 2x2 + 3x) and he bought (4x2 + 3) shirts. The price of each shirt is ₹(x + 5). How much money is left with Raghav?
  • a)
    ₹(2x3 – 18x2 – 15)
  • b)
    ₹(4x2 + 2x + 3)
  • c)
    ₹(x3 – 3x)
  • d)
    ₹(2x3 + 2x2 – 15)
Correct answer is option 'A'. Can you explain this answer?

Total amount Raghav had = ₹(6x3 + 2x2 + 3x)
Cost of one shirt = ₹(x + 5)
Number of shirts he bought = 4x2 + 3
∴ Amount spent by him = ₹(x + 5)(4x2 + 3)
= ₹(4x3 + 20x2 + 3x + 15)
Hence, money left with Raghav
= ₹(6x3 + 2x2 + 3x – 4x3 – 20x2 – 3x – 15)
= ₹(2x3 – 18x2 – 15)

A polynomial of the form ax5 + bx3 + cx2 + dx + e has atmost _______ zeroes.
  • a)
    3
  • b)
    5
  • c)
    7
  • d)
    11
Correct answer is option 'B'. Can you explain this answer?

To find out the maximum number of zeroes a polynomial of the form ax^5 + bx^3 + cx^2 + dx + e can have, we need to consider the degree of the polynomial.

Degree of a polynomial:
The degree of a polynomial is the highest power of the variable (x in this case) in the polynomial.

In this case, the highest power of the variable is 5, so the degree of the polynomial is 5.

Fundamental Theorem of Algebra:
The Fundamental Theorem of Algebra states that a polynomial of degree 'n' has exactly 'n' complex zeroes, counting multiplicities.

Complex zeroes:
Complex zeroes are solutions to the equation of the polynomial in the form a + bi, where 'a' and 'b' are real numbers and 'i' is the imaginary unit (√-1).

Number of zeroes:
Since the degree of the given polynomial is 5, according to the Fundamental Theorem of Algebra, it can have at most 5 complex zeroes.

Multiplicity:
The multiplicity of a zero refers to the number of times it appears as a solution. It is determined by the exponent of the factor (x - r) in the factored form of the polynomial, where 'r' is the zero.

Example:
If the polynomial has a factor (x - r)^2, then 'r' is a zero of multiplicity 2.

Conclusion:
In this case, the polynomial of the form ax^5 + bx^3 + cx^2 + dx + e can have at most 5 zeroes, according to the Fundamental Theorem of Algebra. Therefore, the correct answer is option 'B' - 5.

If the sum of the product of the zeroes taken two at a time of the polynomial f(x) = 2x3 – 3x2 + 4tx – 5 is –8, then the value of t is _______.
  • a)
    2
  • b)
    4
  • c)
    –2
  • d)
    – 4 
Correct answer is option 'D'. Can you explain this answer?

Sumitra verma answered
To find the sum of the product of the zeroes taken two at a time, we need to find the product of each pair of zeroes and then sum them up.

Let the zeroes of the polynomial f(x) = 2x^3 + px^2 + qx + r be a, b, and c.

The product of the zeroes taken two at a time can be expressed as:

ab + ac + bc

Using Vieta's formulas, we know that:

a + b + c = -p/2

ab + ac + bc = q/2

abc = -r/2

Now, we need to find the value of q/2.

From the given information, we can see that the coefficient of x term is q, which is the sum of the zeroes taken two at a time. Hence, q/2 is equal to the sum of the product of the zeroes taken two at a time.

Therefore, the sum of the product of the zeroes taken two at a time is q/2.

11. Find a cubic polynomial whose zeros are α, β, g such that α + β + γ= 6, αβ + βγ + gα = -1 and αβγ = -30.
  • a)
    x3 − 6x2− x +30
  • b)
    x3 + 6x2+ x −30
  • c)
    x3 −x2− 6 x +30
  • d)
    None of these
Correct answer is option 'A'. Can you explain this answer?

Madhuri bajaj answered
To find a cubic polynomial with zeros -2, 0, and 3, we can use the fact that if a polynomial has a zero at a certain value, then it must have a factor of (x - zero).

So, for the given zeros, the factors are: (x - (-2)), (x - 0), and (x - 3).

Simplifying these factors, we get: (x + 2), x, and (x - 3).

To find the cubic polynomial, we multiply these factors together:

(x + 2)(x)(x - 3)

Expanding this expression, we get:

(x^2 + 2x)(x - 3)

Now, we multiply each term in the first expression by each term in the second expression:

x^2(x - 3) + 2x(x - 3)

Expanding further, we get:

x^3 - 3x^2 + 2x^2 - 6x

Combining like terms, we have:

x^3 - x^2 - 6x

Therefore, the cubic polynomial with zeros -2, 0, and 3 is:

f(x) = x^3 - x^2 - 6x

A cubic polynomial with sum of its zeroes, sum of the product of its zeroes taken two at a time and the product of its zeroes as –3, 8, 4 respectively, is _______.
  • a)
    x3 – 3x2 – 8x – 4
  • b)
    x3 + 3x2 – 8x – 4
  • c)
    x3 + 3x2 + 8x – 4
  • d)
    x3 – 3x2 – 8x + 4
Correct answer is option 'C'. Can you explain this answer?

Avni dubey answered
Let the cubic polynomial be $ax^3+bx^2+cx+d$. By Vieta's formulas, we have:

Sum of zeroes = $-\frac{b}{a}$

Sum of product of zeroes taken two at a time = $\frac{c}{a}$

Product of zeroes = $-\frac{d}{a}$

We want the sum of these three quantities, which is:

$-\frac{b}{a}+\frac{c}{a}-\frac{d}{a}=\boxed{\frac{c-b-d}{a}}$

What will be the value of p(3), if 3 is one of zeroes of polynomial p(x) = x3 + bx + D?
  • a)
    3
  • b)
    D
  • c)
    27
  • d)
    0
Correct answer is option 'D'. Can you explain this answer?

Gauri iyer answered
To find the value of p(3), we need to substitute 3 into the polynomial p(x) = x^3 + bx + D.

Let's break down the steps to find the value of p(3):

Step 1: Substitute x with 3 in the polynomial equation:
p(3) = (3)^3 + b(3) + D

Step 2: Simplify the equation:
p(3) = 27 + 3b + D

Since we don't have any specific values for b and D, we cannot simplify the equation any further. Therefore, the value of p(3) is 27 + 3b + D.

Now, let's analyze the given options:

a) 3: This option suggests that p(3) equals 3, but based on the equation p(3) = 27 + 3b + D, there is no guarantee that the value will be exactly 3.

b) D: This option suggests that p(3) equals D, which is one of the variables in the equation. While it is possible for p(3) to equal D if b is zero, we cannot determine the value without more information.

c) 27: This option suggests that p(3) equals 27. While this is a possibility, it is not always the case since the equation also contains the variables b and D. Without specific values for b and D, we cannot determine if p(3) equals 27.

d) 0: This option suggests that p(3) equals 0. Based on the equation p(3) = 27 + 3b + D, we can see that if 27 + 3b + D equals 0, then p(3) will indeed be 0. This is the correct answer since it satisfies the equation.

Therefore, the correct answer is option 'd' - 0.

If sum of all zeros of the polynomial 5x2 – (3 + k)x + 7 is zero, then zeroes of the polynomial 2x2 – 2(k + 11)x + 30 are
  • a)
    3, 5
  • b)
    7, 9
  • c)
    3, 6
  • d)
    2, 5
Correct answer is option 'A'. Can you explain this answer?

Vivek Bansal answered
Sum of zeroes of polynomial
5x2– (3 + k)x + 7 is 
According to question, ((3+k)/5) = 0 ⇒ k = –3
Now, 2x2 – 2(k + 11)x + 30 becomes 2x2 – 16x + 30.
i.e., 2x2 – 16x + 30 = 0 or x2 – 8x + 15 = 0
⇒ x = 3, 5
Hence, zeroes of polynomial 2x2 – 16x + 30 are 3, 5.

A rectangular garden of length (2x3 + 5x2 – 7) m has the perimeter (4x3 – 2x2 + 4) m. Find the breadth of the garden.
  • a)
    (6x2 – 9) m
  • b)
    (–6x2 + 9) m
  • c)
    (2x3 – 7x2 + 11) m
  • d)
    (6x3 + 7x2 + 9) m
Correct answer is option 'B'. Can you explain this answer?

Ritu Saxena answered
Length of the garden = (2x3 + 5x2 – 7) m
Perimeter of the garden = 2 × (length + breadth)
∴ 4x3 - 2x2 + 4 = 2(2x3 + 5x2 – 7 + breadth)
⇒ 2x3 – x2 + 2 = (2x3 + 5x2 – 7) + breadth
So, breadth of the rectangle
= 2x3 – x2 + 2 – 2x3 – 5x2 + 7 = (–6x2 + 9) m

Which of the following graph has more than three distinct real roots?
  • a)
  • b)
  • c)
  • d)
Correct answer is option 'C'. Can you explain this answer?

For more than three distinct real roots the graph must cut x-axis at least four times. So, graph in option (C) has more than three distinct real roots.

Find the other two zeros of the polynomial 2x4 - 3x3 - 3x2 + 6x - 2 if its two roots are √2 and - √2.
  • a)
    1 and 
  • b)
    -1 and 
  • c)
    2 and 1
  • d)
    -2 and 1
Correct answer is option 'A'. Can you explain this answer?

Ritu Saxena answered
2 x4 −3x3− 3x2 +6x− 2
Let the other roots be α and β.
Sum of the roots = 
…(1)
Product of roots = 
√2 + (- √2)αβ  = -1 ⇒ αβ = …(2)
(α - β)2 = (α + β)2 - 4αβ

…(3)
From equation (1) and (3)

If a , b are the zeros of the polynomial x2 - 5x + P such that α - β = 1. What is the value of P?
  • a)
    1/6
  • b)
    6
  • c)
    -6
  • d)
    3
Correct answer is option 'B'. Can you explain this answer?

Ritu Saxena answered
Here α, β are the zeros of x2 - 5x + P
then α + β = 5 …(1)
and αβ = P
α - β = 1 …(2)
Solving (1) and (2) we get
2α = 6 ⇒ α = 3
and β = 5 - 3 = 2
∴ αβ = P = (3) (2) = 6

Length and breadth of a rectangular park are (3x2 + 2x) m and (2x3 – 3) m respectively. Find the area of the park, when x = 3.
  • a)
    1924 m2
  • b)
    1492 m2
  • c)
    1881 m2
  • d)
    1683 m2
Correct answer is option 'D'. Can you explain this answer?

Vivek Bansal answered
Length of rectangular park = (3x2 + 2x) m
Breadth of rectangular park = (2x3 – 3) m
Area of park = length × breadth
= (3x2 + 2x) (2x3 – 3) = (6x5 + 4x4 – 9x2 – 6x) m
For x = 3, 6x5 + 4x4 – 9x2 – 6x
= 6 × 243 + 4 × 81 – 9 × 9 – 6 × 3 = 1683
Hence, area of park = 1683 m2

Chapter doubts & questions for Polynomials - Olympiad Preparation for Class 10 2025 is part of Class 10 exam preparation. The chapters have been prepared according to the Class 10 exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for Class 10 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.

Chapter doubts & questions of Polynomials - Olympiad Preparation for Class 10 in English & Hindi are available as part of Class 10 exam. Download more important topics, notes, lectures and mock test series for Class 10 Exam by signing up for free.

Top Courses Class 10

Related Class 10 Content