Differentiating Harder Trigonometric Functions
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Differentiating Harder Trigonometric Functions
Wednesday, 29 April 2026
h(x)=f(x)1
cosec x=sinx1cosec2 x=sin2x1secx=cosx1cotx=tanx1Rules for differentiating f(x)1
| f(x) | f′(x) |
|---|
| tankx | ksec2kx |
| seckx | kseckx×tankx |
| cotkx | −k cosec2 kx |
| cosec kx | −k cosec kx×cotkx |
Proof for tankx
y=tanxy=cosxsinxu=sinxv=cosxdxdy=cosxdxdu=−sinxdxdy=v(x)2v(x)u′(x)−u(x)v′(x)dxdy=(cosx)2cosx×cosx−−sinx×sinxdxdy=cos2xcos2x+sin2xdxdy=cos2x1dxdy=sec2xProof for cosec kx
y=cosec xy=sinx1y=(sinx)−1y=u−1u=sinxdudy=−u−2dudy=u2−1dxdu=cosxdxdy=dudy×dxdudxdy=cosx×sin2x−1dxdy=sinxcosx×sinx−1dxdy=cotx×−cosec xdxdy=−cotx×cosecxProof for seckx
Todo
arcf(x)=f−1x
arcsinx=sin−1xarccosx=cos−1xarctanx=tan−1xRules for differentiating arcf(x)
| f(x) | f′(x) |
|---|
| arcsinx | 1−x21 |
| arccosx | −1−x21 |
| arctanx | 1+x21 |