Question

if a+b = 5 and a^2 +b^2= 73,
find a^3. +b^3​

Answer 1

Answer:

485

Step-by-step explanation:

• a+b = 5

(a+b)² = 5²

a²+b²+2ab = 25

73 + 2ab = 25

2ab = 25-73

2ab = -48

ab = -24

• a³+b³ = (a+b)(a²-ab+b²)

= 5[(a²+b²) - (ab)]

= 5[73 - (-24)]

= 5[73+24]

= 5[97]

= 485