Question

If sum of the square of the zeroes of the polymials f(x) x^2-8x+k=40 find the value of k

Answer 1

Answer:

7

Step-by-step explanation:

let both the zeroes be A and B

A + B = -b/a =8/1 = 8

AB =c/a = k/1 = k                                      .......(1)

A^2 + B^2 = 40              

(A +B)^2 -2AB = 40

8^2 - 2(k) = 40

64 -2k = 40

64 - 40 = 2k

14 = 2k

k = 7

Answer 2

Answer:

12

Step-by-step explanation:

let one zero be a

second zero be b

polynomial=x^2-8x+k

sum of zeroes=8/1

(a+b)=8

product of zeroes =k/1

ab=k

ATQ

a^2+b^2=40

(a+b)^2 - 2ab =40

(8)^2 - 2×k =40

64-2k=40

2k=24

k=12