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| Question Number 19199 by priyankavarma094@gmail.com last updated on 06/Aug/17 | ||
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| $$\mathrm{y}=\mathrm{tan}\:\mathrm{x}^{\mathrm{tan}\:\mathrm{x}^{\mathrm{tan}\:\mathrm{x}} } \\ $$ | ||
| Answered by NEC last updated on 06/Aug/17 | ||
| ![let u=tan x    y=u^u^u    ln y=u^u ln u  (1/y)dy/dx=u^u ((1/u))+(u^u +ln u)ln u    (dy/dx)=y[(u^u .(1/u) + (u^u +ln u)ln u)]  (dy/dx)=tanx^(tanx^(tanx ) ) {(tanx^(tan x−1)  +(tanx^(tanx ) +ln tan x)ln tan x)}](Q19202.png) | ||
| $${let}\:{u}=\mathrm{tan}\:{x} \\ $$$$ \\ $$$${y}={u}^{{u}^{{u}} } \\ $$$$\mathrm{ln}\:{y}={u}^{{u}} \mathrm{ln}\:{u} \\ $$$$\frac{\mathrm{1}}{{y}}{dy}/{dx}={u}^{{u}} \left(\frac{\mathrm{1}}{{u}}\right)+\left({u}^{{u}} +\mathrm{ln}\:{u}\right)\mathrm{ln}\:{u} \\ $$$$ \\ $$$$\frac{{dy}}{{dx}}={y}\left[\left({u}^{{u}} .\frac{\mathrm{1}}{{u}}\:+\:\left({u}^{{u}} +\mathrm{ln}\:{u}\right)\mathrm{ln}\:{u}\right)\right] \\ $$$$\frac{{dy}}{{dx}}=\mathrm{tan}{x}\:^{\mathrm{tan}{x}\:^{\mathrm{tan}{x}\:} } \left\{\left(\mathrm{tan}{x}\:^{\mathrm{tan}\:{x}−\mathrm{1}} \:+\left(\mathrm{tan}{x}\:^{\mathrm{tan}{x}\:} +\mathrm{ln}\:\mathrm{tan}\:{x}\right)\mathrm{ln}\:\mathrm{tan}\:{x}\right)\right\} \\ $$ | ||
| Commented by NEC last updated on 06/Aug/17 | ||
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| $${thats}\:{if}\:{you}\:{needed}\:\frac{{dy}}{{dx}} \\ $$ | ||