Advertisements
Advertisements
Question
Solution
` ∫ tan^3 \text{x 2x . sec (2x) dx}`
\[ = \int \tan^2 2x . \text{sec 2x tan 2x dx}\]
` ∫ ( \sec^2 \left( 2x \right) - 1 \right) \text{sec (2x) tan ( 2x ) dx `
\[\text{Let sec }\left( 2x \right) = t\]
` ⇒ sec ( 2x ) tan (2x) × 2 = {dt}/{dx} `
` ⇒ sec ( 2x ) tan (2x) dx = {dt}/{2} `
\[Now, \int \tan^3\text{ x 2x} . \text{sec} \left( \text{2x }\right)dx\]
\[ = \frac{1}{2}\int\left( t^2 - 1 \right) dt\]
\[ = \frac{1}{2}\left[ \frac{t^3}{3} - t \right] + C\]
\[ = \frac{1}{2} \left[ \frac{\sec^3 \left( 2x \right)}{3} - \text{sec}\left( \text{2x }\right) \right] + C\]
\[ = \frac{1}{6} \text{sec}^3 \left( \text{2x} \right) - \frac{\text{sec} \left( \text{2x }\right)}{2} + C\]
APPEARS IN
RELATED QUESTIONS
`∫ cos ^4 2x dx `
` ∫ {sin 2x} /{a cos^2 x + b sin^2 x } ` dx
` ∫ \sqrt{tan x} sec^4 x dx `
If \[\int\frac{1}{\left( x + 2 \right)\left( x^2 + 1 \right)}dx = a\log\left| 1 + x^2 \right| + b \tan^{- 1} x + \frac{1}{5}\log\left| x + 2 \right| + C,\] then
\[\int\frac{x^3}{\sqrt{x^8 + 4}} \text{ dx }\]
\[\int {cosec}^4 2x\ dx\]
\[\int\frac{x + 3}{\left( x + 4 \right)^2} e^x dx =\]