How do you solve #10^ { x } \cdot e ^ { x } = 3#?

1 Answer
Dec 19, 2016

#x=(ln|3|)/(ln|10|+1)~~0.33265#

Explanation:

Take the natural log of both sides

#ln|10^xe^x|=ln|3|#

Using the following property of logarithms
we can rewrite the left hand side

#ln|xy|=ln|x|+ln|y|#

#ln|10^x|+ln|e^x|=ln|3|#

Using another property of logarithms we
can rewrite the left hand side again

#ln|x^y|=yln|x|#

#xln|10|+xln|e|=ln|3|#

Recall that #ln|e|=1#

#xln|10|+x=ln|3|#

Factor out an #x# on the left

#x(ln|10|+1)=ln|3|#

Solve for #x#

#x=(ln|3|)/(ln|10|+1)~~0.33265#