Evaluate [(26 + 37)/121]^(3/2)

Question

= [(2√27)^3 + (2√36)^3] / [(2√121)^3]
= [(2√27)^3 + 6] / 1331

and now... I don't know what to do...

the answer is (189/1331)(√7)... BUT I don't know how to get this! Please help me! Thanks.

Answer 1

[(26 + 37)/121]^(3/2)
= [63/121]^(3/2)
= [9*7)^(3/2) / 1331
= [27*√7*√7*√7]/1331
= 27*7*√7/1331
= 189√7/1331

Answer 2

I get what you did up until...

= [27*√7*√7*√7]/1331

Why is it √7 three times instead of √27??? I also don't get why 27 isn't √27...