use common logarithms to solve the equation for x in terms of y. y=e^x + e^-x

Question

Use natural log to solve for x in terms of y.

Answer 1

RONG...yuze loge (ln)

y=e^x +e^-x

ln(y)=x*ln(e)-x*ln(e)

ln(y)=x-x=0

y=1

if yuze log10, remember log10(sumthun)=0.43429448190325408177*ln(sumthun)

Answer 2

Given y=e^x + e^-x

Using common logarithm rules
x=log(1/2(y-√(y^2-4)))+2iπn for all n belongs to Z

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