Answer:
100r^4 + 400r^3 + 600r^2 + 400r + 100
Explanation:
Expanding ( r + 1 )^4 gives :-
r^4 + 4r^3 + 6r^2 + 4r + 1
So multiplying 100 with r^4 + 4r^3 + 6r^2 + 4r + 1 gives :-
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