1.

Evaluate : `int(sinx)/(sqrt(1+sinx))dx`.

Answer» `int(sinx)/(sqrt(1+sinx))dxint((1+sinx)-1)/(sqrt(1+sinx))dx`
`intsqrt(1+sinx)dx-int(dx)/(sqrt(1+sinx))`
`=int(dx)/sqrt(cos^(2)(x//2)+sin^(2)(x//2)+2sin(x//2)cos(x//2))`
`=int[cos(x//2)+sin(x//2)]dx-int(dx)/([cos(x//2)+sin(x//2)])`
`=(2"sin"(x)/(2)-2"cos"(x)/(2))-(1)/(sqrt(2))*int(dx)/((1)/(sqrt(2))"cos"(x)/(2)+(1)/(sqrt(2))"sin"(x)/(2))`
`=(2"sin"(x)/(2)-2"cos"(x)/(2))-(1)/(sqrt(2))*int(dx)/(sin((x)/(2)+(pi)/(4)))`
`=(2"sin"(x)/(2)-2"cos"(x)/(2))-(1)/(sqrt(2))int"cosec"((x)/(2)+(pi)/(4))dx`
`=2("sin"(x)/(2)-"cos"(x)/(2))-(1)/(sqrt(2))xx2log|{:tan((x)/(4)+(pi)/(8)):}|+C`
`=2("sin"(x)/(2)-"cos"(x)/(2))-sqrt(2)log|{:tan((x)/(4)+(pi)/(8)):}|+C`.


Discussion

No Comment Found