For which pairs of functions is f(g(x))=x?
a) f(x)=x^2 and g(x)=1/x
b) f(x)=2/x and g(x)=2/x
c) f(x)x-2/3 and g(x)=2-3x
d) f(x)1/2x-2 and g(x)=1/2x+2

The triangles are similar. what is the value of x? x=

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).