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logarithm

Posted February 5th, 2008 by alpha
in

Solve for x -

$$log_3 (x+1) -1=3+log_3(x-1)$$
$$log_3 (x+1)-log_3(x-1)=4$$
$$log_3\frac{x+1}{x-1}=4$$
$$\frac{x+1}{x-1}=4^3=64$$
$$x+1=64x-64$$
$$63x=65$$
$$x=\frac{65}{63}$$
‹ logarithm evaluate expression ›

Comments

answer

On February 5th, 2008 Structure says:

Solve for x -

$$log_3 (x+1) -1=3+log_3(x-1)$$
$$log_3 (x+1)-log_3(x-1)=4$$
$$log_3\frac{x+1}{x-1}=4$$
$$\frac{x+1}{x-1}=4^3=64$$
$$x+1=64x-64$$
$$63x=65$$
$$x=\frac{65}{63}$$

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