how should i start this
1 - cos^2 theta/ 1 + sin theta = (convert to) sin theta
please help
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how should i start this
1 - cos^2 theta/ 1 + sin theta = (convert to) sin theta
please help
Quote:
Originally Posted by xahjika
Recall that
it says that
prove that it is an identity
1 - cos^2 theta/ 1 + sin theta = sin theta
I have figured it out, and made the edits. But please, in the future, be more clear and add parentheses.Quote:
Originally Posted by xahjika
That identity is not true. Are you sure you're written it correctly?
Edit: Ah right, I was reading it incorrectly also... nevermind.
so sorry i don't know that... i'm just copying what's on the board
Quote:
Originally Posted by Chop Suey
Recall that
with that do i have to foil method this? --> (1 - sin theta)(1 + sin theta)/
1 + sin theta
or cancel the(1 + sin theta).. / 1 + sin theta here --> (1 - sin theta)(1 + sin theta)/ 1 + sin theta
is this right?
red means canceled out
1 - sin^2 theta =
(1 - sin theta) (1 + sin theta)/ (1 + sin theta)=
1 - ( 1 - sin theta) = sin theta
Yes, you have to cancel out like you just did. There are inconsistencies in your work that you may have to fix.Quote:
Originally Posted by xahjika