Trignometry help plssssssssss

1. (sin5x - 2sin3x + sinx) ) / (cos5x - cosx) = tanx

2. tan3x.tan2x.tanx = tan3x - tan2x -tanx

Thank you.

(sin5x - 2sin3x + sinx) ) / (cos5x - cosx) = tanx
(2sin3xcos2x - 2sin3x ) / (-2 sin3x sin2x)
[2sin3x(cos2x-1)]/(-2 sin 3x sin 2x)
-(cos2x-1)/(sin 2x)
-(2cos^2 x - 1 - 1 )/sin2x
-[2(cos^2 x -1)] /sin 2x
(2[1-cos^2 x])/sin 2x
2(sin^2 x) / 2cosx sinx

sinx/cosx
tanx

:)


tan3x.tan2x.tanx = tan3x - tan2x -tanx
there is a method to solve this type of question

tan3x=tan(2x+x)
tan3x=(tan2x+tanx) /(1-tan2xtanx)

cross multiplication
tan3x(1-tan2xtanx)=tan2x+tanx
tan3x - tanx tan2x tan3x = tan2x+tanx
tan3x - tan2x - tanx = tanx tan 2x tan 3x

:)

oh :)
okay i will try :)

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