20 ! can you me with this @exordiumx?

Right-hand side

Since , it follows that

So we can rewrite

We have a cosine difference identity for the denominator:

Since and , we have

Using this in the right-hand side

Notice how we have tiny denominators of 2.If we multiply the numerator and denominator of the entire fraction, we will deal with those twos, as 2 will distribute and cancel.

the answer is d

the answer is in the first quadrant, which make the y-int positive.

since the dots are going down, therefore the correlation is negative

i hope it is right.