Establish the Identity $$\tan \left( x - \frac { \pi } { 4 } \right) = \frac { \tan x - 1 } { 1 + \tan x }$$

Q193: Find the exact value under the

Q194: Solve the equation on the interval

Q195: Solve the problem.<br>-If <span class="ql-formula"

Q196: Find the exact value of the

Q197: Simplify the expression.<br>- <span class="ql-formula" data-value="4

Q199: Solve the problem.<br>-Multiply and simplify:

Q200: Complete the identity.<br>- <span class="ql-formula" data-value="\frac

Q201: Find the exact value under the

Q202: Use the Half-angle Formulas to find

Q203: Find the exact value of the