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Solve `(dy)/(dx) sqrt(1+x+y) =x+y-1` |
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Answer» Putting `sqrt(1+x+y)=v`, we have `x+y-1=v^(2)-2` or `1+(dy)/(dx)=2v(dv)/(dx)` Then, the given transforms to `(2v(dv)/(dx)-1)v=v^(2)-2` or `(dv)/(dx)=(v^(2)+v-2)/(2v^(2))` or `int(2v^(2))/(v^(2)+v-2)dv=intdx` or `2int[1+1/(3(v-1))-4/(3(v+2))]dv=intdx` or `2[v+1/3log|v-1|-4/3log|v+2|]=x+c` where `v=sqrt(1+x+y)` |
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