To evaluate a function at a given input, you have to substitute every occurrence of the variable with that particular value.
So, for the first function, you have

The name of the variable is obviously irrelelvant, so the same goes for the second function:

52+23=75
10+78=88
88+75=163
that's one way
<h3>I'll teach you how to find the period of f(x)=sin(x)</h3>
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A period of a sin is is the length of one cycle.
The original period of the sine curve is 2π.
If x is multiplied by a constant that can change the answer of the period.
The period of the basic sine function f(x) = sin(x) is 2π.
Your Answer Is 2π.
plz mark me as brainliest if this helped :)