Deriving a Reduction Formula

[nycmathguy]

Section 5.4

Correct?

 

[MathLover1]

66. correct

graph

68. correct

 

[nycmathguy]

66. correct

graph

68. correct

I don't see how the graph confirms my answer to be correct.

Verifying a Trigonometric Identity...2

 

[MathLover1]

do you see blue and red lines, on top of each other?
that is a proof

 

[nycmathguy]

do you see blue and red lines, on top of each other?
that is a proof

I don't have a computer. On my phone screen, the curve looks like one color.