You can put this solution on YOUR website! This is simply subtraction of polynomials.
6b^2 - 4b + 3b^4 - (7b^3 + b^4 - 4b)
note: distribute the negative sign to the terms inside the parentheses to eliminate the grouping symbol, thus:
6b^2 - 4b + 3b^4 - 7b^3 - b^4 + 4b
note: combine similar terms in a decreasing order of exponent
3b^4 - b^4 - 7b^3 + 6b^2 - 4b + 4b
note: subtracting 3b^4 - b^4 gives us 2b^4 and adding - 4b + 4b gives us zero (0), thus we have:
2b^4 - 7b^3 + 6b^2 as the final answer
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