Trigonometry Examples

Expand Using Sum/Difference Formulas cos(75)
Step 1
First, split the angle into two angles where the values of the six trigonometric functions are known. In this case, can be split into .
Step 2
Use the sum formula for cosine to simplify the expression. The formula states that .
Step 3
Remove parentheses.
Step 4
Simplify each term.
Tap for more steps...
Step 4.1
The exact value of is .
Step 4.2
The exact value of is .
Step 4.3
Multiply .
Tap for more steps...
Step 4.3.1
Multiply by .
Step 4.3.2
Combine using the product rule for radicals.
Step 4.3.3
Multiply by .
Step 4.3.4
Multiply by .
Step 4.4
The exact value of is .
Step 4.5
The exact value of is .
Step 4.6
Multiply .
Tap for more steps...
Step 4.6.1
Multiply by .
Step 4.6.2
Multiply by .
Step 5
Combine the numerators over the common denominator.
Step 6
The result can be shown in multiple forms.
Exact Form:
Decimal Form: