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The equation is;
tanx - secx = 1
The answer that I get is 90deg. 360deg(n), but the book says it's 180deg. 360deg.(n)
This is what I do
tanx - secx = 1
tanx - secx - 1 = 0
sinx/cos - 1/cosx - 1 = 0
(sinx - 1 - cosx)/cosx = 0
Then multiply both sides by cosx to get:
sinx - 1 - cosx = 0
sinx - 1 - (1-sinx) = 0
sinx - 1 - 1 sinx = 0
2sinx - 2 = 0
2(sinx - 1) = 0
Which means that sinx - 1 must equal zero
sinx = 1
and sin is equal y/r which is equal to one at pi/2 or 90deg.
so, to solve for all solutions we put 90deg. 360deg.(n)
I really don't know what I'm doing wrong. I'm pretty sure it's not using some identity that I don't know. We've only learned the basic identities.
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