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Example Questions
Example Question #1 : Sum And Difference Identities
According to the trigonometric identities,
The trigonometric identity , is an important identity to memorize.
Some other identities that are important to know are:
Example Question #2 : Sum And Difference Identities
Use the sum or difference identity to find the exact value:
Again, here we break up the 165 into and solve using the sin identity:
Example Question #1 : Sum And Difference Identities
Is the following equation an identity?
It cannot be determined from the given information.
No it is not an identity.
Yes it is an identity.
No it is not an identity.
and so this is again not an identity
Example Question #2 : Sum And Difference Identities For Sine
Is the following equation an identity? ?
No it is not an identity
The question cannot be answered based on the information provided.
Yes it is an identity
Example Question #5 : Sum And Difference Identities
Use the sum or difference identity to find the exact value:
Example Question #2 : Sum And Difference Identities
Is the following equation an identity?
No it is not an identity.
Yes it is an identity.
It cannot be determined from the given information.
No it is not an identity.
and due to this inequality, this is not an identity
Example Question #7 : Sum And Difference Identities
Use the sum or difference identity to find the exact value:
Using the identity, we can break up the into
and then solve:
and so the correct answer is
.
Example Question #2 : Sum And Difference Identities For Cosine
No it is not an identity
Yes it is an identity
The answer cannot be determined from the information provided.
Example Question #9 : Sum And Difference Identities
Use the sum or difference identity to find the exact value of .
Here we break up the into
and solve using the sin identity:
and so here the credited answer is
.
Example Question #10 : Sum And Difference Identities
Evaluate the exact value of:
In order to solve , two special angles will need to be used to solve for the exact values.
The angles chosen are and
degrees, since:
Write the formula for the cosine additive identity.
Substitute the known variables.
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