Let , where , , , and are all non-zero real numbers. If , then ______.
Solutions — 2
Solution 1
Since , we have:
Using the properties of sine and cosine concerning odd and even multiples of , we have:
and
This simplification arises because is an odd multiple of which makes sine function remain the same due to its periodicity, while cosine changes sign.
Hence, we can rewrite the equation as:
which leads to:
Now, let's find using an analogous argument:
Since is an even multiple of , both and functions will not change sign with respect to their respective offsets, thus we have:
and
Substitute these values into the expression for :
Therefore, the answer is .
Solution 2
Since , we have:
which simplifies to . Therefore, we can deduce that .
Thus,
Therefore, the answer is .
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