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The solution of differential equation `(1-xy + x^(2) y^(2))dx = x^(2) dy` isA. tan xy = log |cx|B. tan (y/x) = tan log |cx|C. xy = tan log |cx|D. None of these |
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Answer» Correct Answer - C `(1-xy+x^(2)y^(2))dx = x^(2) dy` `(1-(xy)+(xy)^(2))dx = x^(2) dy` Let xy = v. `y = (v)/(x)` `therefore" "(dy)/(dx)=(x*(dv)/(dx)-v)/(x^(2))` `x^(2)dy = xdv - v dx` So,`" "(1-v+v^(2))dx = xdv - vdx` `rArr" "(1+v^(2))dx = xdv` `rArr" "int (dv)/(1+v^(2))=int(dx)/(x)` `rArr" "tan^(-1)v=log|x|+log c` `rArr" "tan^(-1)v = log |cx|` `rArr" "v = tan log |cx|` `rArr" "xy = tan log |cx|` |
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