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Verify the identity Sin^3x + (Sinx) cos^2x = sinx?
AHHH! Trig is so confusing!
5 Answers
- panic modeLv 71 decade agoFavorite Answer
divide everything by sin(x) and you get
sin^2x+cos^2x=1 which is basic identity
- RameshwarLv 71 decade ago
L.H.S. = sin^3x + sinx cos^2x
= sinx ( sin^2x + cos^2x )
= sinx (1)= sinx =R.H.S.
- Brach ZLv 41 decade ago
Show that sin³x + sin x cos²x = sin x.
Recall that sin²x + cos²x = 1.
Therefore,
sin³x + sin x cos²x
= sin³x + sin x (1 - sin²x)
= sin³x + sin x - sin³x
= sin x.
Or alternatively,
sin³x + sin x cos²x
= (sin x) (sin²x + cos²x)
= (sin x) (1)
= sin x.
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- MechEng2030Lv 71 decade ago
factoring out a sin(x) on the l.h.s:
sin(x)[sin²(x) + cos²(x)] = sin(x)*1 = sin(x)
