Question

Ifa+b+c=5 and ab+bc+ca=10, then prove that a^3+b^3+c^3-3abc=-25​

Answer 1

Step-by-step explanation:

a + b + c = 5

square Karne per

(a + b + c)² = 25

a²+b²+c²+2(ab+bc+ac) = 25

a² + b² + c² + 2*10 = 25

a² + b² + c² = 5

a³ + b³ + c³ - 3abc

(a+b+c){a²+b²+c²-(ab+bc+ac)}

5 {5 - 10}

5 * -5

-25