simpilfy the expression:
[4x7]4
four and severn are the exponents
(^) indicates an exponent online. (x^2 = x squared.)
(4x^7)^4 = (4x^7)(4x^7)(4x^7)(4x^7) = 256x^28
When multiplying terms, you add the value of the exponents.
I hope this helps.