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Zeroes of the quadratic polynomial x2 + 3x -(a + 2)(a - 1) is
  • a)
    - (a + 2) and - (a - 1)
  • b)
    (a + 2) and - (a - 1)
  • c)
    - (a + 2) and (a - 1)
  • d)
    None of these
Correct answer is option 'C'. Can you explain this answer?
Most Upvoted Answer
Zeroes of the quadratic polynomial x2 + 3x -(a + 2)(a - 1) isa)- (a +...
The given polynomial is: P(x) = x2 + 3x - (a + 2)(a - 1)
Zeros of the polynomial obtained by taking P(x) = 0
x2 + 3x - (a + 2)(a - 1) = 0
x2 + (a + 2)x - (a - 1)x - (a + 2)(a - 1) = 0
x[x + a + 2] - (a - 1)[x + a + 2] = 0
[x + a + 2][x - (a - 1)] = 0
x = -(a + 2) or x = a - 1
Hence, the zeros of the polynomial are (a + 2) and (a - 1).
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Community Answer
Zeroes of the quadratic polynomial x2 + 3x -(a + 2)(a - 1) isa)- (a +...
Finding the zeroes of a quadratic polynomial

To find the zeroes of a quadratic polynomial, we can use the quadratic formula or factorization method. The quadratic formula states that for a quadratic equation of the form ax2 + bx + c = 0, the roots are given by:

x = (-b ± √(b2 - 4ac)) / 2a

Alternatively, we can use the factorization method to find the roots. If we can factor the quadratic polynomial into the form (x - r)(x - s), then the roots are given by r and s.

Applying the formula to the given polynomial

The given quadratic polynomial is x2 + 3x - (a - 2)(a - 1). To find the roots, we can apply the quadratic formula:

x = (-3 ± √(32 - 4(1)(-(a-2)(a-1)))) / 2(1)
= (-3 ± √(9 + 4a2 - 4a + 4)) / 2
= (-3 ± √(4a2 - 4a + 13)) / 2

Thus, the roots are (-3 + √(4a2 - 4a + 13)) / 2 and (-3 - √(4a2 - 4a + 13)) / 2.

Simplifying the expression

We can simplify the expression by noticing that the coefficients of the quadratic polynomial are symmetrical. That is, the coefficient of x2 is 1, the coefficient of x is 3, and the constant term is -(a-2)(a-1), which is also symmetrical. Therefore, the roots of the polynomial must be symmetrical as well.

In other words, if r is a root of the polynomial, then so is 3 - r. To see this, we can use the factorization method. If (x - r) is a factor of the polynomial, then so is (x - (3-r)), since:

(x - (3-r)) = -x + 3 + r
(x - r) + (-x + 3 + r) = 3

Therefore, the roots of the polynomial must be of the form (-3 ± k) / 2, where k is some expression involving a.

Using this form, we can simplify the expression for the roots as follows:

(-3 + k) / 2 = (-3 + √(4a2 - 4a + 13)) / 2
k = √(4a2 - 4a + 13) + 3

(-3 - k) / 2 = (-3 - √(4a2 - 4a + 13)) / 2
k = -√(4a2 - 4a + 13) + 3

Therefore, the roots are (-3 + √(4a2 - 4a + 13)) / 2 and (-3 - √(4a2 - 4a + 13)) / 2, which are equivalent to -(a-2) and (a-1), respectively.

Conclusion

The zeroes of the quadratic polynomial x2 + 3x - (a-2)(a-1) are -(a-2) and (a-
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Zeroes of the quadratic polynomial x2 + 3x -(a + 2)(a - 1) isa)- (a + 2) and - (a - 1)b)(a + 2) and - (a - 1)c)- (a + 2) and (a - 1)d)None of theseCorrect answer is option 'C'. Can you explain this answer?
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Zeroes of the quadratic polynomial x2 + 3x -(a + 2)(a - 1) isa)- (a + 2) and - (a - 1)b)(a + 2) and - (a - 1)c)- (a + 2) and (a - 1)d)None of theseCorrect answer is option 'C'. Can you explain this answer? for Class 10 2025 is part of Class 10 preparation. The Question and answers have been prepared according to the Class 10 exam syllabus. Information about Zeroes of the quadratic polynomial x2 + 3x -(a + 2)(a - 1) isa)- (a + 2) and - (a - 1)b)(a + 2) and - (a - 1)c)- (a + 2) and (a - 1)d)None of theseCorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for Class 10 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Zeroes of the quadratic polynomial x2 + 3x -(a + 2)(a - 1) isa)- (a + 2) and - (a - 1)b)(a + 2) and - (a - 1)c)- (a + 2) and (a - 1)d)None of theseCorrect answer is option 'C'. Can you explain this answer?.
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