Question

se a+b=5 e a.b=-8, o valor de a²+4a.b+b² é?

Answer 1

(a+b) = 5

(a+b)² = 5²

a²+b² + 2.(a.b) = 25

a²+b² + 2.(-8) = 25

a²+b² - 16 = 25

a²+b² = 25 +16

a²+b² = 41

a²+b² +4(ab)

41 + 4(-8)

41 - 32= 9