Question

Si: a + b = 12 ; a^2+ b^2= 86 hallar: a^3+ b^3

Answer 1

Respuesta:

684

Explicación paso a paso:

a + b = 12

a^2 + b^2 = 86

( a + b )^2 = 12^2

a^2 + b^2 + 2ab = 144

86 + 2ab = 144

2ab = 144 - 86

2ab = 58

ab = 58 / 2

ab = 29

a^3 + b^3 = ( a + b ) ( a^2 + b^2 - ab )

a^3 + b^3 = 12 ( 86 - 29 )

= 12 ( 57 )

a^3 + b^3 = 684