Finding the inverse of y=x^(1/3) and y=3(2)^x

[thomasrules]

yea ok but wait how do u find the inverse of like

y=(x)^(1/3)

y=3(2)^x

whats the formula is not in the book

BTW i can't do those equations in latex...

 

[courtrigrad]

interchange x and y, and solve for y.

 

[thomasrules]

answer says y=x^3

 

[quasar987]

which is exactly what courtrigrad's method predicts:

1° interchange x and y: y=(x)^(1/3) --> x=y^(1/3)

2° solve for y: x=y^(1/3) --> y=x^3

 

[Checkfate]

make sure you understand algebra thomas, if you don't know all the algebra rules now, learn them b4 it's too late!

 

[HallsofIvy]

For y= 3(2^x), again do what courtrigrad said: Swap x and y to get x= 3(2^y) and solve for y by taking logs of both sides:
log(x)= log(3(2^y))= ylog(2)+ log(3)
y log(2)= log(x)- log(3)= log(x/3)
y= log(x/3)/log(2).