Answer:
The answer is d.
Step-by-step explanation:
As we know, sin x= cos (90°-x)
sin 18° = cos (90°-18°)
= cos 72°.
Similarly, sin 72°= cos (90°-72°)
= cos 18°
But, sin 55°= cos (90°-55°)
= cos 35°
The multiplier is (1/4) or .25
RemarkIf you don't start exactly the right way, you can get into all kinds of trouble. This is just one of those cases. I think the best way to start is to divide both terms by x^(1/2)
Step OneDivide both terms in the numerator by x^(1/2)
y= 6x^(1/2) + 3x^(5/2 - 1/2)
y =6x^(1/2) + 3x^(4/2)
y = 6x^(1/2) + 3x^2 Now differentiate that. It should be much easier.
Step TwoDifferentiate the y in the last step.
y' = 6(1/2) x^(- 1/2) + 3*2 x^(2 - 1)
y' = 3x^(-1/2) + 6x I wonder if there's anything else you can do to this. If there is, I don't see it.
I suppose this is possible.
y' = 3/x^(1/2) + 6x
y' =

Frankly I like the first answer better, but you have a choice of both.
a. Recall that

For
, we have

By integrating both sides, we get

If
, then

so that

We can shift the index to simplify the sum slightly.

b. The power series for
can be obtained simply by multiplying both sides of the series above by
.

c. We have

