Answer:
256h^28·k^8
Step-by-step explanation:
This is a pretty straightforward application of the rules of exponents:
(ab)^c = a^c·b^c
(a^b)^c = a^(b·c)
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Applying the first rule to eliminate parentheses, you get ...
= 4^4·(h^7)^4·(k^2)^4
Applying the second rule to combine exponents, you get ...
256·h^28·k^8 . . . . . matches the last choice
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An exponent signifies repeated multiplication. That is ...
k^2 = k·k . . . . . the exponent of 2 means k appears 2 times in the product
Then ...
(k^2)^4 = (k^2)·(k^2)·(k^2)·(k^2) . . . . . k^2 appears 4 times in the product
of course, we know k^2 = k·k, so our expression expands to ...
(k^2)^4 = (k·k)·(k·k)·(k·k)·(k·k) = k^8
Once you understand where these rules come from and what exponents mean, I believe it should make more sense.
