Question

Find the value of (5a-7b)^3+(9c-5a)^3+(7b-9c)^3

Answer 1

this is somewhat a long solution bt u can do this by using this formula..... a³ + b³ + c³ = (a + b + c) (a² + b² + c²– ab – bc – ca) + 3abc.
I hope this will help u..

Answer 2

Thanks for a BRAINLY question!!!!

We have, (5a-7b)^3+(9c-5a)^3+(7b-9c)^3

Let us consider A = (5a-7b)
                         B = (9c-5a)
                         C = (7b-9c)

Now, A+B+C =  (5a-7b)+(9c-5a)+(7b-9c) = 0

Since, A+B+C= 0

then, A^3 + B^3 + C^3 = 3ABC

This means,


(5a-7b)^3+(9c-5a)^3+(7b-9c)^3

= 3ABC

= 3 {(5a-7b)(9c-5a)(7b-9c)}

Hope it helps!!!!