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1. ### Prove Identity: cos(2x) / 1 + sin(2x) = tan (pi/4 - x)?

LHS=cos(2x) / 1 + sin(2x) =(cox^2x- sin^2x) /(cox^2x+sin^2x +2sinx.cosx) =(cosx +sinx).(cosx...x) ..............=(tanpi/4 - tanx)/(1+tanpi/4tanx) ..............=(1-tanx)/(1+tanx) ..............=LHS at "A"

2 Answers · Science & Mathematics · 22/11/2009

2. ### Trig Identity Question?

LHS = -tan^2x / (-cot^2 x) = tan^4 x RHS = tan^2x sec^2x - (sec^2x - 1) = tan^2x sec^2x - tan^2x = tan^2x(sec^2x - 1) = tan^2x ( tan^2 x) = tan^4 x LHS = RHS

1 Answers · Science & Mathematics · 16/01/2014

3. ### challenging trig identity please help!?

LHS = sin(x) + sin(x + 14π/3) + sin(x - 8π/3) = sin(x) + sin(x + 2π/3) + sin(x - 2π...

3 Answers · Science & Mathematics · 05/03/2013

4. ### PreCalc 12 Help, Identities?

LHS =(cos^2x/sin^2x)*sinx =cos^2x/sinx =2cos^2x/sinx-cos^2x/sinx =2/(sec^2x*sinx)-(cosx/sinx)*cosx =2cscx/sec^2x-cosx/cotx =RHS

1 Answers · Science & Mathematics · 16/01/2013

5. ### Please help me prove a trig identity :) (cscx-cotx)^2=(1-cosx)/(1+cosx)?

LHS: (cscx - cotx)^2 = (1/sinx - cosx/sinx)^2 = (1 - cosx)^2/sin^2(x) By trig identity...cancel out so left hand side simplifies to (1 - cosx)/(1 + cosx) Now LHS = RHS

4 Answers · Science & Mathematics · 27/01/2011

6. ### HELP?!10PTS Trig. Prove each identity:........?

a). LHS: sinx + tanx Now I multiply them to cosx/cosx meaning I multiply...cosθ)] (sinθ + cosθ) cancel out = (sinθ - cosθ)/cosθ = sinθ/cosθ - cosθ/cosθ = tanθ - 1 = LHS Proved.

3 Answers · Science & Mathematics · 15/05/2012

7. ### Trig identities question?

LHS = cot(x) / tan(x) = (cos(x)/sin(x)) / (sin(x)/cos(x)) = cos²(x) / sin²(x) = (1-sin²(x)) / (1-cos²(x)) = RHS

3 Answers · Science & Mathematics · 10/05/2009

8. ### trig identities is this even possible?

LHS = cos(x)/(1-sin(x)) - sec(x) = cos(x)(1+sin(x))/[(1+sin(x))(1-sin(x))] - 1/cos(x) = cos(x)(1+sin(x)/(1-sin²(x)) - 1/cos(x) = cos(x)(1+sin(x))/cos²(x) - 1/cos(x) = (1+sin(x))/cos(x) - 1/cos(x) = sin(x)/cos(x) = tan(x) = RHS

5 Answers · Science & Mathematics · 25/01/2010

9. ### Physics Manometer Question?

On the LHS, P1 = Patm + rho*g*H. where rho is the density of water...

1 Answers · Science & Mathematics · 14/05/2015

10. ### TRIG IDENTITIES: How to prove that (- 6 - 6sinx) / 5cosx = (- 6cosx)/(5(1 - sinx))?

LHS = -6/5 * (1 + sin(x))/cos(x) * (1 - sin(x))/(1 - sin(x)) [Multiply the top...

3 Answers · Science & Mathematics · 09/12/2011

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