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For what value of k, the zeroes of a quadratic polynomial p(x)=2x²+9x+(k+2k-1) are negative reciprocal of each other?
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For what value of k, the zeroes of a quadratic polynomial p(x)=2x²+9x+...
Introduction:
A quadratic polynomial is an expression of the form ax² + bx + c, where a, b, and c are constants. The zeroes of a quadratic polynomial are the values of x that make the polynomial equal to zero. In this problem, we are given a quadratic polynomial and we need to find the value of k such that the zeroes of the polynomial are negative reciprocals of each other.

Method:
To find the zeroes of the given quadratic polynomial, we can use the quadratic formula. The quadratic formula states that the zeroes of a quadratic polynomial ax² + bx + c are given by:

x = (-b ± √(b² - 4ac)) / 2a

If the zeroes of the polynomial are negative reciprocals of each other, then we can write:

x₁ = -1/x₂

Substituting this into the quadratic formula, we get:

-1/x₂ = (-b ± √(b² - 4ac)) / 2a

Multiplying both sides by x₂, we get:

-1 = (-b ± √(b² - 4ac))x₂ / 2a

Solving for x₂, we get:

x₂ = (-2a) / (-b ± √(b² - 4ac))

Since we want the zeroes of the polynomial to be negative reciprocals of each other, we can set x₁ = -1/x₂ and solve for k.

Solution:
The given quadratic polynomial is:

p(x) = 2x² + 9x (k - 2k + 1)

Expanding the polynomial, we get:

p(x) = 2x² + 9x (k - 2k + 1)
= 2x² + 9x (1 - k)

The discriminant of the quadratic formula is:

b² - 4ac = (9(1-k))² - 4(2)(0)

Simplifying, we get:

b² - 4ac = 81(1 - 2k)

Since we want the zeroes of the polynomial to be negative reciprocals of each other, we can set x₁ = -1/x₂ and solve for k. Substituting the values for the zeroes from the quadratic formula, we get:

x₁ = (-9 ± √(81(1 - 2k))) / 4

x₂ = (-2) / (-9 ± √(81(1 - 2k)))

Setting x₁ = -1/x₂ and simplifying, we get:

(9 ± √(81(1 - 2k))) / 2 = -2 / x₂

Multiplying both sides by x₂ and simplifying, we get:

(9 ± √(81(1 - 2k)))x₂ = -4

Substituting the value of x₂ from the quadratic formula, we get:

(9 ± √(81(1 - 2k))) (-9 ± √(81(1 - 2k))) = -8(1 - k)

Simplifying, we get:

81(1 - 2k) - 81(1 - 2k) ± 18√(81(1 - 2k)) =
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For what value of k, the zeroes of a quadratic polynomial p(x)=2x²+9x+...
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For what value of k, the zeroes of a quadratic polynomial p(x)=2x²+9x+(k+2k-1) are negative reciprocal of each other? for Class 10 2024 is part of Class 10 preparation. The Question and answers have been prepared according to the Class 10 exam syllabus. Information about For what value of k, the zeroes of a quadratic polynomial p(x)=2x²+9x+(k+2k-1) are negative reciprocal of each other? covers all topics & solutions for Class 10 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for For what value of k, the zeroes of a quadratic polynomial p(x)=2x²+9x+(k+2k-1) are negative reciprocal of each other?.
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