What is the coefficient of $a^2b^2$ in $(a+b)^4\left(c+\dfrac{1}{c}\right)^6$?
Question:
What is the coefficient of $a^2b^2$ in $(a+b)^4\left(c+\dfrac{1}{c}\right)^6$?
Answer:
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What is the coefficient of $a^2b^2$ in $(a+b)^4\left(c+\dfrac{1}{c}\right)^6$?
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