[Index]
Introduction Essence Memorizing Understanding Summarizing ExamplesExample
1
Example 2
Example 3
Example 4
Example 5
Example 6
Example 7
Example 8
General
ideas
Exercises Final
thoughts
 |
Example 5--Page 2
This time we don't multiply the
left by 
. Instead, we
multiply it by 
.
Now, we want the first factor to be
. To do so, we need change functions 
to 
.
Try to simplify the terms on the
top of first factor. If we use the Product to Sum formulas to convert them
to addition, we'll get 
, 
from , 
; and , 
from , 
, which yields like terms of 
.
We want the first factor to be . Because the right side of the identity doesn't
have a denominator, so we need to cancel 
. By using the Sum to
Product formulas on the top of first factor, we get:
Then we use a Double Angle formula to convert 
to 
and canceling
. We have:
