Question

If alpha and beta a roots of quadratic equation X square - 2 x minus 7 equal to zero find the value of Alpha square plus beta square

Answer 1

Answer:

• alpha+beta=2but I am not sure

Answer 2

Answer:

18

Step-by-step explanation:

x square - 2x - 7 = 0

α + β = $\frac{-b}{a}$ = $\frac{2}{1}$

αβ = $\frac{c}{a}$ = $\frac{-7}{1}$

as we know that

                                                             [ ∴(α+β)² - 2αβ = α² + β²]

= (2)²-2(-7)

=4+14

=18

∴ α²+β² = 18