How do you evaluate and simplify (12^(3/5)*8^(3/5))^5?

1 Answer
Aug 31, 2016

884736.

Explanation:

The Expression=(12^(3/5)*8^(3/5))^5

=(12^(3/5))^5*(8^(3/5))^5...............["Rule" : (ab)^m=a^m.b^m]

=12^((3/5*5))*8^((3/5*5))............["Rule" : (a^m)^n=a^((m*n))]

=12^3*8^3

=1728*512=884736.

Alternatively,

The Expression=(12^(3/5)*8^(3/5))^5

={(12*8)^(3/5)}^5..................["Rule" : a^m*b^m=(ab)^m]

=(96)^(3/5*5).......................["Rule" : (a^m)^n=a^((m*n))]

=96^3

=(100-4)^3.

Here, we use, (x-y)^3=x^3-y^3-3xy(x-y), and get,

96^3=100^3-4^3-3(100)(4)(100-4)

=1000000-64-1200(100-4)

=1000000-64-120000+4800

=1004800-120064

=884736, as before!

Enjoy Maths.!