Advertisements
Advertisements
प्रश्न
By using the properties of the definite integral, evaluate the integral:
`int_0^(pi/2) cos^2 x dx`
उत्तर
Let `I = int_0^(pi/2) cos^2 x dx` ....(i)
and `I = int_0^(pi/2) cos^2 (pi/2 - x) dx`
`= int_0^(pi/2) sin^2 x dx` ....(ii) `[∵ int_0^a f (x) dx = int_0^a f (a - x) dx]`
Adding (i) and (ii), we get
`2 I = int_0^(pi/2) cos^2 x dx + int_0^(pi/2) sin^2 x dx`
`= int_0^(pi/2) (sin^2 x + cos^2 x) dx`
`= int_0^(pi/2) dx = [x]_0^(pi/2)`
`= pi/2`
⇒ `I = pi/4.`
APPEARS IN
संबंधित प्रश्न
Prove that: `int_0^(2a)f(x)dx=int_0^af(x)dx+int_0^af(2a-x)dx`
By using the properties of the definite integral, evaluate the integral:
`int_((-pi)/2)^(pi/2) sin^2 x dx`
By using the properties of the definite integral, evaluate the integral:
`int_0^(2x) cos^5 xdx`
The value of `int_0^(pi/2) log ((4+ 3sinx)/(4+3cosx))` dx is ______.
Evaluate the definite integrals `int_0^pi (x tan x)/(sec x + tan x)dx`
\[\int\limits_0^k \frac{1}{2 + 8 x^2} dx = \frac{\pi}{16},\] find the value of k.
Evaluate : `int "e"^(3"x")/("e"^(3"x") + 1)` dx
Choose the correct alternative:
`int_(-9)^9 x^3/(4 - x^2) "d"x` =
`int_1^2 1/(2x + 3) dx` = ______
State whether the following statement is True or False:
`int_(-5)^5 x/(x^2 + 7) "d"x` = 10
Evaluate `int_1^3 x^2*log x "d"x`
`int_2^3 x/(x^2 - 1)` dx = ______
If f(x) = |x - 2|, then `int_-2^3 f(x) dx` is ______
`int_{pi/6}^{pi/3} sin^2x dx` = ______
`int_0^pi x sin^2x dx` = ______
`int_0^9 1/(1 + sqrtx)` dx = ______
Find `int_0^(pi/4) sqrt(1 + sin 2x) "d"x`
Show that `int_0^(pi/2) (sin^2x)/(sinx + cosx) = 1/sqrt(2) log (sqrt(2) + 1)`
`int_(-1)^1 (x^3 + |x| + 1)/(x^2 + 2|x| + 1) "d"x` is equal to ______.
Evaluate the following:
`int_(-pi/4)^(pi/4) log|sinx + cosx|"d"x`
`int_((-pi)/4)^(pi/4) "dx"/(1 + cos2x)` is equal to ______.
`int_0^(2"a") "f"("x") "dx" = int_0^"a" "f"("x") "dx" + int_0^"a" "f"("k" - "x") "dx"`, then the value of k is:
Evaluate: `int_(pi/6)^(pi/3) (dx)/(1 + sqrt(tanx)`
`int_a^b f(x)dx` = ______.
The value of the integral `int_(-1)^1log_e(sqrt(1 - x) + sqrt(1 + x))dx` is equal to ______.
`int_0^1|3x - 1|dx` equals ______.
The value of the integral `int_0^1 x cot^-1(1 - x^2 + x^4)dx` is ______.
Evaluate: `int_0^π 1/(5 + 4 cos x)dx`
If `int_0^(π/2) log cos x dx = π/2 log(1/2)`, then `int_0^(π/2) log sec dx` = ______.
`int_-1^1 |x - 2|/(x - 2) dx`, x ≠ 2 is equal to ______.
Evaluate: `int_(-π//4)^(π//4) (cos 2x)/(1 + cos 2x)dx`.
Evaluate : `int_-1^1 log ((2 - x)/(2 + x))dx`.
Evaluate the following integral:
`int_0^1 x(1-x)^5 dx`
Evaluate the following integral:
`int_-9^9x^3/(4-x^2)dx`
Solve the following.
`int_0^1e^(x^2)x^3dx`
Solve the following.
`int_0^1e^(x^2)x^3dx`