Comments (9) on “Find the angle measure that makes the statement true. sin 25 = cos”
You can solve this one easily with your calculator. BUT ... you can solve it even more easily with your brain.
If you ever hung around on a rainy day looking at a right triangle and thinking about sines and cosines, you probably noticed that the sine of any angle is the cosine of its complement, and the cosine of any angle is the sine of its complement.
Since the sine and cosine functions are cofunctions, they are complementary. The format for this is that sinx=cos(90-x). This works for secant and cosecant and tangent and cotangent. So, sin25°=cos65°.
You can solve this one easily with your calculator. BUT ... you can solve it even more easily with your brain.
If you ever hung around on a rainy day looking at a right triangle and thinking about sines and cosines, you probably noticed that the sine of any angle is the cosine of its complement, and the cosine of any angle is the sine of its complement.
The complement of 37° is 53° .
So the cos(37°) = the sin(53°).
sin 25° = cos 65°
Step-by-step explanation:
We have trigonometric result
sin θ = cos (90 -θ)
Here we asked to convert Sin 25° in to cosine.
So,
sin 25° = cos (90 -25) = cos 65°
sin 25° = cos 65°
Sin (25°) = cos (65°)
That is because there is an identity that establishes that the sin (x) = cos (90 -x), and 25 = 90 - 65
We know that sin(x) = cos(90°-x). In that sense, we know that:
sin(25°) = cos(90°-25°) = cos(65°)
If you put both values in a calculator, we get that:
sin(25°) = 0.4226
cos(65°) = 0.4226
Therefore: Sin 25° = Cos 65°
Sin α = cos ( 90° - α )
sin 25° = cos 65°
Thank you.
65.
You simply have to put cos-1(sin(25))
Since the sine and cosine functions are cofunctions, they are complementary. The format for this is that sinx=cos(90-x). This works for secant and cosecant and tangent and cotangent. So, sin25°=cos65°.
[tex]We\ know:\\\\\cos(90^o-\alpha)=\sin\alpha\\\\\cos37^o=\cos( 90^o-53^o)=\sin53^o[/tex]
Cos 65
(90-sin value)