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Trigonometry Examples
Step 1
Write as an equation.
Step 2
Interchange the variables.
Step 3
Step 3.1
Rewrite the equation as .
Step 3.2
Divide each term in by and simplify.
Step 3.2.1
Divide each term in by .
Step 3.2.2
Simplify the left side.
Step 3.2.2.1
Cancel the common factor of .
Step 3.2.2.1.1
Cancel the common factor.
Step 3.2.2.1.2
Divide by .
Step 3.3
Take the inverse cosine of both sides of the equation to extract from inside the cosine.
Step 3.4
Subtract from both sides of the equation.
Step 3.5
Divide each term in by and simplify.
Step 3.5.1
Divide each term in by .
Step 3.5.2
Simplify the left side.
Step 3.5.2.1
Cancel the common factor of .
Step 3.5.2.1.1
Cancel the common factor.
Step 3.5.2.1.2
Divide by .
Step 3.5.3
Simplify the right side.
Step 3.5.3.1
Move the negative in front of the fraction.
Step 4
Replace with to show the final answer.
Step 5
Step 5.1
To verify the inverse, check if and .
Step 5.2
Evaluate .
Step 5.2.1
Set up the composite result function.
Step 5.2.2
Evaluate by substituting in the value of into .
Step 5.2.3
Cancel the common factor of .
Step 5.2.3.1
Cancel the common factor.
Step 5.2.3.2
Divide by .
Step 5.3
Evaluate .
Step 5.3.1
Set up the composite result function.
Step 5.3.2
Evaluate by substituting in the value of into .
Step 5.3.3
Simplify each term.
Step 5.3.3.1
Apply the distributive property.
Step 5.3.3.2
Cancel the common factor of .
Step 5.3.3.2.1
Cancel the common factor.
Step 5.3.3.2.2
Rewrite the expression.
Step 5.3.3.3
Cancel the common factor of .
Step 5.3.3.3.1
Move the leading negative in into the numerator.
Step 5.3.3.3.2
Cancel the common factor.
Step 5.3.3.3.3
Rewrite the expression.
Step 5.3.4
Combine the opposite terms in .
Step 5.3.4.1
Add and .
Step 5.3.4.2
Add and .
Step 5.3.5
The functions cosine and arccosine are inverses.
Step 5.3.6
Cancel the common factor of .
Step 5.3.6.1
Cancel the common factor.
Step 5.3.6.2
Rewrite the expression.
Step 5.4
Since and , then is the inverse of .