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Solve `[xsin^2(y/x)-y]dx+x dy=0; y=pi/4`when `x=1.` |
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Answer» Correct Answer - `cot(y/x)=log_(e)|ex|` `[xsin^(2)(y/x)-y]dx+xdy=0` or `(dy)/(dx)=v+(xdv)/(dx)` Therefore, given equation reduces to `v+x(dv)/(dx)=v-sin^(2)v` or `x(dv)/(dx) = -sin^(2)v` or `"cosec "^(2)vdv=-(dx)/(x)` Integrating both sides, we get `-cotv=-log|x|-logC` or `cot(y/x)=log|Cx|`...............(2) Now, `y=pi/4` at `x=1`. `therefore cot(pi/4) = log|C|` or `1=log C` or C=e Substituting C=e in equation (2), we get `cot(y/x)=log|ex|` This is the required solution of the given differential equation |
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