How do you solve 4^x= 74x=7?

1 Answer
Jul 17, 2015

I found: x=1.4036x=1.4036

Explanation:

If you can use a pocket calculator (or tables) you could change it into a log using the definition of logarithm:
log_ab=x->a^x=blogab=xax=b
where in your case you get:
log_4(7)=xlog4(7)=x
you can now change base of your log to evaluate it using a pocket calculator (for example, using the base ee of the natural logarithm, lnln):
x=log_4(7)=(ln(7))/(ln(4))=1.4036x=log4(7)=ln(7)ln(4)=1.4036