INVERSE OF A FUNCTION

To find the inverse ( f^-1)(x) of a function f(x); follow the following steps:

Example: Find the inverse of

y = 1-2x

1) Write the original equation.

y = 1-2x

2) Solve it in terms of x.

y = 1 -2x

-2x = -1 + y

x = (1-y)/2

3) Interchange y and x in the result of step 2.

x = (1-y)/2 ==> y = (1-x)/2

4) The inverse function f^-1(x) of f(x) = 1 -2x

is therefore f^-1(x) = (1-x)/2

Convert Radians to Degrees and Vice Versa

A) To convert radians to degrees

Multiply radians by 180 degrees/pi
Example:

3pi/4 ==> degrees

3pi/4 x 180 degrees/pi (pi will cancel out)

540/4 = 135 degrees

B) To convert degrees to radians

Multiply degrees by pi/180 degrees
Example:
60 degrees ==> radians

60 degrees x pi/180 degrees ( degrees will cancel out)

60pi/180 = pi/3