1. cosxtanx-1+tanx-cosx=0

2. 2sinxtanx- tanx- 2sinx +1 = 0

Help would be greatly appreciated

- Thank you

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- May 20th 2007, 08:19 AMiamdenis2 Trig problems for Tuesday, Help please
1. cosxtanx-1+tanx-cosx=0

2. 2sinxtanx- tanx- 2sinx +1 = 0

Help would be greatly appreciated

- Thank you - May 20th 2007, 08:43 AMJhevon
Here's the first one.

When faced with trig problems like these, what you want to do is first see if any trig identities can siplify things a bit. If not, treat each trig function as a variable, and facter as you would normally. for instance, the first one is:

tan^2x - 4tanx = 0

if we thought of tangent as a variable, say y, the problem would become:

y^2 - 4y = 0

that's a regular quadratic equation, you should have no problem with that. that is the basis of how i approached the problem. try the second one and tell me if you get it

EDIT: i see that you changed question 1. anyway, it doesn't matter, the same method is applicable. try them - May 20th 2007, 08:56 AMiamdenis
yeah i was kind of over thinking the problem that i changed, cause just as i posted it i figured out how easy it was. But for the other ones im not sure if im going in the right direction, for ex #2

2sinxtanx- tanx- 2sinx +1 = 0

2sin²/cosx - sinx/cosx - 2sinxcosx/cosx + cosx/cosx= 0

is that what i should be doing? or am i over doing it again? lol

- May 20th 2007, 09:10 AMJhevon
yes, you are over doing it again i'm afraid, lol. calm down :D

2sinxtanx - tanx - 2sinx + 1 = 0 .......factor out the common term from each pair

=> tanx(2sinx - 1) - (2sinx - 1) = 0 ....now we have a common 2sinx - 1, factor it out

=> (2sinx - 1)(tanx - 1) = 0

can you take it from here? - May 20th 2007, 09:15 AMiamdenis
- May 20th 2007, 09:18 AMJhevon
yeah, a lot of students get paranoid with trig. just calm down, take a deep breath and approach them with a cool head. if seeing trig makes you sqirm, just replaced them with a variable as i suggested earlier, and you will be able to think straight. another thing that often scares students is logarithms, especially ones that involve ln and e, don't fall into that trap