Trigonometry Examples

Expand the Trigonometric Expression cos(3x)^2-sin(3x)^2
Step 1
Since both terms are perfect squares, factor using the difference of squares formula, where and .
Step 2
Simplify terms.
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Step 2.1
Simplify each term.
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Step 2.1.1
Use the triple-angle identity to transform to .
Step 2.1.2
Apply the sine triple-angle identity.
Step 2.2
Simplify each term.
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Step 2.2.1
Use the triple-angle identity to transform to .
Step 2.2.2
Apply the sine triple-angle identity.
Step 2.2.3
Apply the distributive property.
Step 2.2.4
Multiply by .
Step 2.2.5
Multiply by .
Step 3
Expand by multiplying each term in the first expression by each term in the second expression.
Step 4
Simplify terms.
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Step 4.1
Combine the opposite terms in .
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Step 4.1.1
Reorder the factors in the terms and .
Step 4.1.2
Subtract from .
Step 4.1.3
Add and .
Step 4.1.4
Reorder the factors in the terms and .
Step 4.1.5
Add and .
Step 4.1.6
Add and .
Step 4.2
Simplify each term.
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Step 4.2.1
Rewrite using the commutative property of multiplication.
Step 4.2.2
Multiply by by adding the exponents.
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Step 4.2.2.1
Move .
Step 4.2.2.2
Use the power rule to combine exponents.
Step 4.2.2.3
Add and .
Step 4.2.3
Multiply by .
Step 4.2.4
Multiply by by adding the exponents.
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Step 4.2.4.1
Move .
Step 4.2.4.2
Multiply by .
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Step 4.2.4.2.1
Raise to the power of .
Step 4.2.4.2.2
Use the power rule to combine exponents.
Step 4.2.4.3
Add and .
Step 4.2.5
Multiply by .
Step 4.2.6
Multiply by by adding the exponents.
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Step 4.2.6.1
Move .
Step 4.2.6.2
Multiply by .
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Step 4.2.6.2.1
Raise to the power of .
Step 4.2.6.2.2
Use the power rule to combine exponents.
Step 4.2.6.3
Add and .
Step 4.2.7
Multiply by .
Step 4.2.8
Multiply .
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Step 4.2.8.1
Multiply by .
Step 4.2.8.2
Raise to the power of .
Step 4.2.8.3
Raise to the power of .
Step 4.2.8.4
Use the power rule to combine exponents.
Step 4.2.8.5
Add and .
Step 4.2.9
Multiply by .
Step 4.2.10
Multiply by .
Step 4.2.11
Multiply by .
Step 4.2.12
Rewrite using the commutative property of multiplication.
Step 4.2.13
Multiply by by adding the exponents.
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Step 4.2.13.1
Move .
Step 4.2.13.2
Use the power rule to combine exponents.
Step 4.2.13.3
Add and .
Step 4.2.14
Multiply by .
Step 4.2.15
Multiply by by adding the exponents.
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Step 4.2.15.1
Move .
Step 4.2.15.2
Multiply by .
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Step 4.2.15.2.1
Raise to the power of .
Step 4.2.15.2.2
Use the power rule to combine exponents.
Step 4.2.15.3
Add and .
Step 4.2.16
Multiply by .
Step 4.2.17
Multiply by .
Step 4.2.18
Multiply by by adding the exponents.
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Step 4.2.18.1
Move .
Step 4.2.18.2
Multiply by .
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Step 4.2.18.2.1
Raise to the power of .
Step 4.2.18.2.2
Use the power rule to combine exponents.
Step 4.2.18.3
Add and .
Step 4.2.19
Multiply by .
Step 4.2.20
Multiply .
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Step 4.2.20.1
Multiply by .
Step 4.2.20.2
Raise to the power of .
Step 4.2.20.3
Raise to the power of .
Step 4.2.20.4
Use the power rule to combine exponents.
Step 4.2.20.5
Add and .
Step 4.3
Simplify by adding terms.
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Step 4.3.1
Combine the opposite terms in .
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Step 4.3.1.1
Reorder the factors in the terms and .
Step 4.3.1.2
Add and .
Step 4.3.1.3
Add and .
Step 4.3.1.4
Reorder the factors in the terms and .
Step 4.3.1.5
Subtract from .
Step 4.3.1.6
Add and .
Step 4.3.2
Subtract from .
Step 4.3.3
Add and .