thanks
Jan 25, 2015 #3 Eric Manuel 7 0 Jimmy Johnson said: Can you give the entire problem? all thats given is that
Jan 25, 2015 #5 Eric Manuel 7 0 MostlyHarmless said: What is the question? What are you asked to find? what is =cos2x
Jan 25, 2015 #6 MostlyHarmless 345 15 What is x supposed to be? Is the given problem in terms of t? Are you trying to solve for t and then plug that value in for x?
What is x supposed to be? Is the given problem in terms of t? Are you trying to solve for t and then plug that value in for x?
Jan 25, 2015 #7 Eric Manuel 7 0 oh my bad its cos2t its basically asking you to use the double angle formula but im not sure how to find those values
oh my bad its cos2t its basically asking you to use the double angle formula but im not sure how to find those values
Jan 25, 2015 #8 Jimmy Johnson 27 0 If you're simply trying to find t, then use cot = 1/tan... If you have a value for t why do you need to use the double angle identities?
If you're simply trying to find t, then use cot = 1/tan... If you have a value for t why do you need to use the double angle identities?
Jan 25, 2015 #9 Eric Manuel 7 0 to find what cos2t is .... you can find what tan is from cot then i drew a triangle and got the hypot to be sqrt(41) but how do i do that math formula for cos2t = cos^2(t) - sin^2(t)
to find what cos2t is .... you can find what tan is from cot then i drew a triangle and got the hypot to be sqrt(41) but how do i do that math formula for cos2t = cos^2(t) - sin^2(t)
Jan 25, 2015 #11 Eric Manuel 7 0 Jimmy Johnson said: Are you forbidden from using a calculator? teacher said u can use it but need to know how to do it without one for test
Jimmy Johnson said: Are you forbidden from using a calculator? teacher said u can use it but need to know how to do it without one for test
Jan 25, 2015 #12 Jimmy Johnson 27 0 Well that may have been useful information at the start... you have cot = -5/4, find what tan is then recall tan = sin/cos ... or recall cot = cos/sin...
Well that may have been useful information at the start... you have cot = -5/4, find what tan is then recall tan = sin/cos ... or recall cot = cos/sin...
Jan 25, 2015 #15 Jimmy Johnson 27 0 You had the method right. Find the reference triangle then using toa soh cah find the sine, cosine or tan values to be substituted into the given identity. You might find this link useful: http://www.mhhe.com/math/precalc/ba...tt01paga_s/ch06/downloads/pc/ch06section3.pdf
You had the method right. Find the reference triangle then using toa soh cah find the sine, cosine or tan values to be substituted into the given identity. You might find this link useful: http://www.mhhe.com/math/precalc/ba...tt01paga_s/ch06/downloads/pc/ch06section3.pdf
