Answer:

Step-by-step explanation:
we know that
In this problem
The value of x represent the radius of the circle
so
Applying the Pythagoras theorem in the right triangle of the figure, you can find the radius of the circle O
see the attached figure to better understand the problem



square root both sides

I'm not sure but I think it is the first one
Answer:
The derivative is

Step-by-step explanation:
The function is given by

Differentiate with respect to x, we get

Answer:
a
Step-by-step explanation: