Question

Si a+b=3
ab=1
hallar a^4+b^4

Answer 1

A+b = 3  ab = 1
hallar a⁴ + b ⁴ 
Fórmaula
(a+b)² = a² + ab + b ²
= ( (a²) + (b)² )² = (a²)² + (a²)(b²) + (b²)²
= (a+b ) ⁴ = a⁴ + (ab)² + (b) ⁴
= (3)⁴ = a⁴ + (1)² + b ⁴
= 81 = a ⁴ + 1 + b⁴
=81 - 1 = a⁴ + b ⁴
80 = a⁴ + b ⁴