if alpha and beta are the zeroes of the polynomial f(x)=x2-6x+k find the value of k, such that alpha square + beta square =40
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f(x)= x²-6x+k
Let alpha and beta are the zeroes of the quadratic polynomial f(x).
Now,
alpha ²+beta²= 40 -----------(i)
Therefore, alpha +beta= -b/a= -(-6)/1
= alpha + beta = 6 -------------(ii)
& alpha × beta= c/a= k/1
= alpha × beta= k ---------------(iii)
So from (i) ,
alpha² + beta²= 40
(alpha+beta)²- 2 alpha× beta= 40
(6)² - 2× k= 40
36-2k= 40
-2k= 40-36
-2k= 4
k= -4/2
Therefore, k= -2
Hope it helps you buddy.
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Let alpha and beta are the zeroes of the quadratic polynomial f(x).
Now,
alpha ²+beta²= 40 -----------(i)
Therefore, alpha +beta= -b/a= -(-6)/1
= alpha + beta = 6 -------------(ii)
& alpha × beta= c/a= k/1
= alpha × beta= k ---------------(iii)
So from (i) ,
alpha² + beta²= 40
(alpha+beta)²- 2 alpha× beta= 40
(6)² - 2× k= 40
36-2k= 40
-2k= 40-36
-2k= 4
k= -4/2
Therefore, k= -2
Hope it helps you buddy.
Please mark me as brainlist
keshaw521:
Please mark me as brainlist
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