Sum and Difference Cosine Formulas (Finding Exact ...
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Sum and Difference Cosine Formulas (Finding Exact Values) Date ___________________ Period _______
The Cosine of two angles being added together... cos (! + ") = cos ! cos " – sin ! sin "
The Cosine of the difference of two angles... cos (! – ") = cos ! cos " + sin ! sin "
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express 75° using common angles 0° 30° 45° 60° 90° 120° 135° 150° 180° cos 75°
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express 15° using common angles 0° 30° 45° 60° 90° 120° 135° 150° 180° cos 15°
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express
7π using common angles 12 0π 2π 3π 4π 6π 8π 12 12 12 12 12 12
9π 12
10π 12π 12 12
cos 7π 12
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 2
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express
π using common angles 12 0π 2π 3π 4π 6π 8π 12 12 12 12 12 12
9π 12
10π 12π 12 12
cos π
12
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express 165° using common angles 0° 30° 45° 60° 90° 120° 135° 150° 180° cos 165°
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 3
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express
5π using common angles 12 0π 2π 3π 4π 6π 8π 12 12 12 12 12 12
9π 12
10π 12π 12 12
cos 5π 12
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: cos 10° cos 20° – sin 10° sin 20°
cos 105° cos 45° + sin 105° sin 45°
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 4
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: 7π
cos 12 cos
7π π π + sin 12 sin 12 12
5π
cos 18 cos
5π π π – sin 18 sin 18 18
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 5
Name _________________________________
Sum and Difference Cosine Formulas (Finding Exact Values) Date ___________________ Period _______
The Cosine of two angles being added together... cos (! + ") = cos ! cos " – sin ! sin "
The Cosine of the difference of two angles... cos (! – ") = cos ! cos " + sin ! sin "
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express 75° using common angles 0° 30° 45° 60° 90° 120° 135° 150° 180° cos 75°
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express 15° using common angles 0° 30° 45° 60° 90° 120° 135° 150° 180° cos 15°
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express
7π using common angles 12 0π 2π 3π 4π 6π 8π 12 12 12 12 12 12
9π 12
10π 12π 12 12
cos 7π 12
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 2
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express
π using common angles 12 0π 2π 3π 4π 6π 8π 12 12 12 12 12 12
9π 12
10π 12π 12 12
cos π
12
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express 165° using common angles 0° 30° 45° 60° 90° 120° 135° 150° 180° cos 165°
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 3
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: express
5π using common angles 12 0π 2π 3π 4π 6π 8π 12 12 12 12 12 12
9π 12
10π 12π 12 12
cos 5π 12
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: cos 10° cos 20° – sin 10° sin 20°
cos 105° cos 45° + sin 105° sin 45°
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 4
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
Find the exact value of the following expressions: 7π
cos 12 cos
7π π π + sin 12 sin 12 12
5π
cos 18 cos
5π π π – sin 18 sin 18 18
Sum cos (! + ") = cos ! cos " – sin ! sin "
Difference cos (! – ") = cos ! cos " + sin ! sin "
© iTutoring.com Sum and Difference Cosine Formulas (Finding Exact Values) Pg. 5
