Math - another question

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"In the expansion of (2-ax)^5 the coefficient of x^2 is 5. Find the value of a".

I know I have to use the binomial theorem to help me, but I don't know how.

  • Never Mind! -

    I got it. :)

  • Math - another question -

    How did u get it?

  • Math - another question -

    According to the binomial theorem, the term with x^2 would be the third term. I plugged my known values into the "formula" for the third term, and made it equal to 5. Then I solved for a. Sorry, my explanation is kind of vague.

  • Math - another question -

    Cool, I appreciate you responding to my question.

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