Answer:
Sin 90°=1
Step-by-step explanation:
A unit circle is a circle with a radius of 1 .Because the radius is 1, it is possible to directly measure the sine, cosine and tangent.
<em>using the unit circle where 90° is the limit as the hypotenuse approaches the vertical y-axis which is positive.</em>
Sine=opposite/hypotenuse
Sin=O/H
<u>Applying the limits</u>
Sine 90°=1/1= 1
cos 90° =0/1 =0
or
When the angle formed at the origin of the unit circle in the 1st quadrant is 0°, cos 0°=1 sin0°=0 and tan 0°=0
When we increase the angle until it is 90°, cos 90°=0, sin 90°=1 and tan 90°=undefined