SOLUTION: If a=2^x+2^-x and b=2^x-2^-x, find the expression for a^2+b^2.

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Question 1176440: If a=2^x+2^-x and b=2^x-2^-x, find the expression for a^2+b^2.
Answer by ikleyn(52925) About Me  (Show Source):
You can put this solution on YOUR website!
.

    a^2 = 2^(2x) + 2*(2^x)*(2^(-x)) + 2^(-2x)

    b^2 = 2^(2x) - 2*(2^x)*(2^(-x)) + 2^(-2x)

  ---------------------------------------------- Add the two lines


    a^2 + b^2 = 2^(2x+1)            + 2^(-2x+1).      ANSWER

Solved.