Question

Sendo m²+n²= 20 e mn=10, calcule o valor de (m+n)².

Answer 1

Resposta:

${(m+n)}^{2} = {m}^{2} + 2mn + {n}^{2} \\ = {m}^{2} + {n}^{2} + 2mn \\ = 20 + 2.10 = 20 + 20 = 40$