use an inverse trig function to write theta as a function of x

(There is a right triangle drawn.
The hypotenuse is 2.
Theta is the angle between the base and the hypotenuse.
The base/adjacent side of theta is labeled(x + 1)
The side opposite theta does not have a value.)

Use an inverse trig function to write theta as a function of x:

a) theta = sqrt [4 - (x + 1)^2] all divided by 2

b)theta = arccos [(x + 1)/2]

c)theta = arctan[(x + 1)/2]

d)theta = arcsin [2/(x + 1)]

How do I do this? I'm leaning towards B, the inverse cosine because only the adjacent side and hypotenuse are given. The opposite side is not given, and there is already a variable x in the given adjacent side.

Am I on the right track? If not, please explain. Thank you.

2 answers

Leaning? Lord, solve the triangle.

so cosine Theta=(x+1)/2

So lean on B.
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