Half-Angle Formulas...5

Section 5.5

 

correction:

 

Where did I go wrong? Can you point out my error?

 

that correction does not count now, I have noticed you have tan(u)=-5/13 but GIVEN tan(u)=-5/12 for ex.43

 

If the correction does not count now, do you mean my answer is correct?

 

no, look again at 43.

GIVEN is tan(u)=-5/12 NOT tan(u)=-5/13

 

I was going to continue on in Section 5.5 but after reading your replies, I think working on 41 and 44 is needed.

 

first cot(u)=3-> cot(18.43 °) I quadrant (given pi<u<3pi/2)

then
sin(u)=1/sqr(10)
cos(u)=3/sqr(10)







.....rationalize

 

Although I got it wrong, I am learning. I am getting better each day.