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# Maths trig question A2 watch

1. Hey guys
I need help solving this question:
cosec^2x + cotx - 1 = 0
I get two solutions which are correct but I can't get the other two
2. (Original post by Remainresilient_)
Hey guys
I need help solving this question:
cosec^2x + cotx - 1 = 0
I get two solutions which are correct but I can't get the other two
3. (Original post by SeanFM)
I subbed in 1+cot^2x for cosec^2x and I got cot^2x + cotx = 0
4. (Original post by Remainresilient_)
I subbed in 1+cot^2x for cosec^2x and I got cot^2x + cotx = 0
Perfect so far. After that?
5. (Original post by SeanFM)
Perfect so far. After that?
then I let cotx = a
so I got a^2 + a = 0
factorised that got a(a+1)=0
made a = 0 then a = -1
1/tan x = 0 (this must be wrong because I didn't get the correct two solutions from this)
1/tanx = -1. so tan x = -1 (this was correct as it led me to half the number of solutions)
There are 4 solutions and I can only get two of them correct so far
6. (Original post by Remainresilient_)
then I let cotx = a
so I got a^2 + a = 0
factorised that got a(a+1)=0
made a = 0 then a = -1
1/tan x = 0 (this must be wrong because I didn't get the correct two solutions from this)
1/tanx = -1. so tan x = -1 (this was correct as it led me to half the number of solutions)
There are 4 solutions and I can only get two of them correct so far
Were you given the range of the solutions?
7. (Original post by SeanFM)
Were you given the range of the solutions?
The range is 0 to 2pi
8. (Original post by Remainresilient_)
The range is 0 to 2pi
Okay.

If cotx = 0, as you've said 1/tanx = 0, so what does that suggest about tanx?

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Updated: October 27, 2015
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