Computer Forums Maths homework (yes, I know!)
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 10-30-2005, 11:08 AM #1 Fully Optimized     Join Date: Feb 2005 Posts: 2,776 Maths homework (yes, I know!) I know I shouldn't be asking. Gah, Maths is so pointless, but I'm stuck with it until January. Can anybody help me out? I've got to Show that: a) (1-cosēt)(1+cotanēt)=1 b) tanθ + cotanθ = 1/ cosθsinθ c) sinθtanθ+cosθ = secant θ I don't need to solve the equations or find any values, I've just got to show the statements are true. I don't know where to start with these three buggers. Anybody? Pointless trig is my main sticking point. Any ideas? __________________ __________________ Master of common sense. If you don't like it, stop reading.
 10-30-2005, 11:36 AM #2 Golden Master     Join Date: Jul 2005 Posts: 7,459 Re: Maths homework (yes, I know!) well u can prove them right by calculating them. Sin, Cos and Tan are angles, u need to have a calculator which knows these. If u don't u can use the one on windows. Other than that it goes beyond my understanding. __________________ __________________ 0_o
 10-31-2005, 03:13 AM #3 BSOD   Join Date: May 2005 Posts: 2,734 Re: Maths homework (yes, I know!) a) (1-cosēt)(1+cotanēt)=1 (1-(1-sinēt))(1+(cscēt-1))=1 (sinēt)(cscēt)=1 sinēt(1/sinēt)=1 1=1 b) tan(t) + cotan(t) = 1/(cos(t)sin(t)) sin(t)/cos(t) + cos(t)/sin(t) = 1/(cos(t)sin(t)) sinē(t)/(sin(t)cos(t)) + cosē(t)/(sin(t)cos(t)) = 1/(cos(t)sin(t)) (sinē(t) + cosē(t))/(sin(t)cos(t)) = 1/(cos(t)sin(t)) 1/(sin(t)cos(t)) = 1/(cos(t)sin(t)) c) sin(t)tan(t) + cos(t) = sec(t) sin(t)(sin(t)/cos(t)) + cos(t) = sec(t) sinē(t)/cos(t) +cosē(t)/cos(t) = sec(t) (sinē(t) + cosē(t))/cos(t) = sec(t) 1/cos(t) = sec(t) sec(t) = sec(t)
 10-31-2005, 03:15 AM #4 BSOD   Join Date: May 2005 Posts: 2,734 Re: Maths homework (yes, I know!) please delete this post
 10-31-2005, 06:53 AM #5 Site Team   Join Date: Mar 2005 Posts: 13,081 Re: Maths homework (yes, I know!) sooo much to do...>_<
 10-31-2005, 10:51 AM #6 BSOD   Join Date: May 2005 Posts: 2,734 Re: Maths homework (yes, I know!) It's not too hard as long as you know your trig identities. __________________