Question

If alfa and beta are the roots of 9x²+10x+11 then alfa²+beta²

Answer 1

Answer:

alpha^2 + beta^2 = -98/81

Step-by-step explanation:

=> 9x²+10x+11

a= 9, b= 10 and c= 11

If alpha and beta are the zeroes

alpha^2 + beta^2 = (alpha + beta)^2 - 2alpha x beta ------> 1

=> alpha + beta = -b/a

=> -10/9 ------> 2

=> alpha x beta = c/a

=> 11/9 --------> 3

Substitute 2 and 3 in 1

=> (-10/9)^2 - 2(11/9)

=> 100/81 - 22/9

=> 100 - 198/81

=> -98/81

=> alpha^2 + beta^2  = -98/81