Math (Trig) a.s.a.p, thanks!
posted by Hailey on .
verify the identities:
1.) 2tanx-(1+tanx)^2 = -secx
*the ãis only over the 3*
any help is greatly appreciated!!
ã is supposed to represent square root.
so for number 2
it's 1/2 (square root 3 cosx-sinx)
LS = 2sinx/cosx - (1+sinx/cosx)^2
= 2sinx/cosx - ((cosx + sinx)/cosx)
= 2sinx/cosx - (cos^2 x + 2sinxcosx + sin^2 x)/cos^2 x
= (2sinxcosx -(1 + 2sinxcosx))/cos^2 x
= -1/cos^2 x
= -sec^2 x
you had -secx on the right side
I think you made a typo
2. LS = cosxcos330 + sinxsin330
but sin 330 = -sin30 = -1/2
and cos 330 = cos30 = √3/2
= (√3/2)cosx - 1/2 sinx
= 1/2(√3 cosx - sinx)
Why don't you try the third one.
Change everything to sines and cosines
let me know how you did.
for the third one you had
Your lack of brackets made this ambiguous.
I tried (1+cos2x)/sinx=cotx and tested with 40º, did not work
I tried 1+cos^2 x/sinx=cotx and tested with 40º, did not work
I tried 1+(cos2x/sinx)=cotx and tested with 40º, did not work
check your typing of the question.