Using a Right Triangle

[nycmathguy]

Section 4.3

Part (a)

Side y is opposite angle theta.

Part (b)

Side x is opposite 90° - theta.

Part (c)

sin (theta) = cos(90° - theta) because they are co-functions.

Yes?

Here we end with Section 4.3.

 

[MathLover1]

yes

part c: In other words, the sine of an angle equals the cosine of its complement.

 

[nycmathguy]

yes

part c: In other words, the sine of an angle equals the cosine of its complement.

Perfect.