SOLUTION: Find trigonometric functions of angle α in a rightangled triangle with hypotenuse = 13cm and leg (catheti) = 12 cm

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Question 1083096: Find trigonometric functions of angle α in a rightangled triangle with hypotenuse = 13cm and leg (catheti) = 12 cm
Found 2 solutions by Alan3354, KMST:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
It's a right triangle with sides a = 5, b = 12 & c = 13.
------
Angle C is the right angle = 90 degs.
sin(C) = 1
cos(C) = 0
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Angle A is the smallest angle opposite side a.
sin(A) = 5/13
cos(A) = 12/13
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Angle B is the angle opposite side b.
sin(B) = 12/13
cos(B) = 5/13
======================
For all angles,
tan = sin/cos
cot = 1/tan
sec = 1/cos
csc = 1/sin



Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Without a picture with side lengths and angle alpha labeled,
or some other way to figure out if angle alpha is opposite or adjacent to the 12-cm leg,
I cannot give you the trigonometric functions of angle alpha ,
but I can draw your triangle as triangle ABC, with right angle at A,
and give you the trigonometric functions of acute angles B and C.
You will have o figure out which one is alpha .
B is the angle adjacent to the 12-cm leg, C is opposite the 12-cm leg.
You need the length, x , of leg AC.
For that you use the Pythagorean theorem.
Applied to this triangle, it says
x%5E2%2B%2812cm%29%5E2=%2813cm%29%5E2
x%5E2%2B144cm%5E2=169cm%5E2
x%5E2=169cm%5E2-144cm%5E2
x%5E2=25cm%5E2
x=5cm
With that length you can calculate values of all trigonometric functions for the acute angles.
Then you use the definitions for trigonometric ratios for a right triangle
sin%28angle%29=%22opposite_leg%22%2Fhypotenuse , and cos%28angle%29=%22adjacent_leg%22%2Fhypotenuse .
You may know tangent defined as
tan%28angle%29=sin%28angle%29%2Fcos%28angle%29 ,
or you may have learned it as
tan%28angle%29=%22opposite_leg%22%2F%22adjacent_leg%22 .
If you are expected to calculate cotangent, secant and cosecant, you would use
cot%28angle%29=1%2Ftan%28angle%29 , sec%28angle%29=1%2Fcos%28angle%29 and csc%28angle%29=1%2Fsin%28angle%29 .
As a tutor, I would prefer to see you figure it out from this point on,
but I will give you the answers because
you are not here to be persuaded to do the work,
and the website tells me that tutors "MUST SHOW ALL WORK."