How to solve this problem?
2 Answers
Answer d is correct.
Explanation:
I would use identities.
We know that
#(5/13)^2 + cos^2x = 1#
#cos^2x = 1 - 25/169#
#cos^2x = 144/169#
#cosx = +-12/13#
However, we know the answer must be negative because of the C-A-S-T rule, which is shown in the following picture.
So only sine is positive on
Now we can use the quotient identity, which states that
#costheta = x/r#
#sintheta = y/r#
#tantheta = y/x#
Now notice that
#(y/r)/(x/r) = y/x# or#sintheta/costheta = tantheta#
#tantheta = sintheta/costheta = (5/13)/(-12/13) = -5/12#
So answer d.
Hopefully this helps!
Explanation:
We know that
So, the opposite and hypotenuse are equal to
For this problem, we can simply consider the opposite and hypotenuse to be
The hypotenuse of a triangle is its longest side.
Using Pythagoras' theorem:
Now,
The interval that we are provided with is
In the second quadrant, all values of
So,
Therefore,
In conclusion, the final answer is