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    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
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    (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
    What was your method?
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    (Original post by SeanFM)
    What was your method?
    I subbed in 1+cot^2x for cosec^2x and I got cot^2x + cotx = 0
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    (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?
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    (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
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    (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?
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    (Original post by SeanFM)
    Were you given the range of the solutions?
    The range is 0 to 2pi
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    (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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