Question

23. If one zero of the quadratic polynomial f(x) = 4x^2 - 8kx + 8x - 9 is negative of other, then find
zeroes of kx^2 + 3kx + 2.​

Answer 1

Answer:

Let,

One zero be 'a'. So, the other zero becomes '-a'

f(x) = 4x² - 8(k-1)x - 9 = 0

a + (-a) = -B/A

a - a = - [-8(k-1)] / 4

0 = 8(k-1)

k-1 = 0

k = 1

Let,

The other polynomial be,

p(x) = kx² + 3kx + 2 = 0

Putting the values of 'k'

=> (1)x² + 3(1)x + 2 = 0

x² + 3x + 2 = 0

x² + 1x + 2x + 2 = 0

x(x + 1) + 2(x + 1) = 0

(x + 1) (x + 2) = 0

Therefore,

x = -1 and -2.

Therefore the zeroes of p(x) are -1 and -2.

Hope this helped you!! :) :)