Question

3. Si a +b = 6 y ab = 3, calcula el valor de
«a² + b²>
a)20 b)42 c)36 d)22 e)30​

Answer 1

Respuesta:

$a + b = 6 \\ ab = 3 \\ ( a + b) {}^{2} = a {}^{2} + b {}^{2} + 2ab \\ {6}^{2} = a {}^{2} + b {}^{2} + 2(3) \\ 36 - 6 = {a}^{2} + {b}^{2} \\ 30 = {a}^{2} + {b}^{2}$