Advertisements
Advertisements
Question
Integrate the following functions with respect to x :
`(sin4x)/sinx`
Solution
`int (sin4x)/sinx "d"x = int (sin2(2x))/sinx * "d"x`
[sin 2A = 2 sin A cos A]
= `int (2sin 2x cos 2x)/sinx "d"x`
= `2 int (2sinx cosx * cos 2x)/sinx * "d"x`
= `4int cos 2x cos x * d"x`
= `2 int 2 cos 2x cosx * "d"x`
= `2 int [cos(2x + x) + cos(2x - x)] "d"x`
[2 cos A cos B = cos(A + B) + cos(A – B)]
= `2 int (cos 3x + cosx) "d"x`
= `2 int cos 3x "d"x + 2int cos x "d"x`
= `2 (sin3x)/3 + 2 sin x + "c"`
= `2 [(sin 3x)/3 + sin x] + "c"`
APPEARS IN
RELATED QUESTIONS
Find the volume of solid generated by rotating the area bounded by x2+y2 =36 and the lines x = 0, x = 3 about X -axis.
Evaluate : `int _0^1 ("x" . ("sin"^-1 "x")^2)/sqrt (1 - "x"^2)` dx
Integrate the following functions with respect to x :
`(3 + 4cosx)/(sin^2x)`
Integrate the following functions with respect to x :
sin2 5x
Integrate the following functions with respect to x :
`(3x + 4) sqrt(3x + 7)`
Integrate the following functions with respect to x :
`(8^(1 + x) + 4^(1 - x))/2^x`
Integrate the following functions with respect to x :
`1/(sqrt(x + 3) - sqrt(x - 4))`
Integrate the following with respect to x:
x sec x tan x
Integrate the following with respect to x:
`"e"^(2x) sinx`
Integrate the following with respect to x:
`"e"^(-x) cos 2x`
Integrate the following with respect to x:
`"e"^(tan^-1 x) ((1 + x + x^2)/(1 + x^2))`
Find the integrals of the following:
`1/(6x - 7 - x^2)`
Find the integrals of the following:
`1/sqrt(9 + 8x - x^2)`
Integrate the following with respect to x:
`(2x + 1)/sqrt(9 + 4x - x^2)`
Integrate the following functions with respect to x:
`sqrt((6 - x)(x - 4))`
Integrate the following functions with respect to x:
`sqrt(9 - (2x + 5)^2`
Integrate the following functions with respect to x:
`sqrt(81 + (2x + 1)^2`
Choose the correct alternative:
`int (x + 2)/sqrt(x^2 - 1) "d"x` is
Choose the correct alternative:
`int sin sqrt(x) "d"x` is