Question and Answers Forum |
IntegrationQuestion and Answers: Page 35 |
![]() |
if I_n =∫xsin^n x dx and I_n = −((xsin^(n−1) x cosx )/n) +((sin^n x )/n^2 )+f(n)I_(n−2) then f(n) = ? |
∫_0 ^1 ((sin x(cos^2 x−cos^2 (π/5))(cos^2 x−cos^2 ((2π)/5)))/(sin 5x)) dx =? |
∫_(π/2) ^π (dx/((sin x−2cos x)^2 )) =? |
![]() |
∫((sin2x)/( (√(cos^4 x+1))))dx |
Calculate 𝛗=∫_0 ^( 1) (( ln(x ))/(1 + x^( 2) )) dx =^? −G ∼ Solution ∼ 𝛗 = ∫_0 ^( 1) {Σ_(k=0) ^∞ (−1)^( k) x^( 2k) ln(x) }dx = Σ_(k=0) ^∞ (−1 )^( k) ∫_0 ^( 1) x^( 2k) ln(x) dx =^(i.b.p) Σ_(k=0) ^∞ (−1 )^( k) {[(x^( 1+2k) /(1+2k)) ln(x ) ]_0 ^1 −(1/(1+2k))∫_0 ^( 1) x^( 2k) dx } = Σ_(k=0) ^∞ (( (−1)^(1+k) )/(( 1 + 2k )^( 2) )) = − G ( Catalan constant ) ∴ 𝛗 = − G ■ m.n |
![]() |
∫ (dx/(cot^3 x sin^7 x)) =? |
Prove that ∫_0 ^(π/2) ((sin^2 x)/((sin x+cos x)))dx=(1/( (√2)))log ((√2)+1) |
Evaluate ∫_0 ^π (x/(a^2 cos^2 x+b^2 sin^2 x))dx |
∫ ((3x^(16) +5x^(14) )/((x^5 +x^2 +1)^4 ))dx |
∫ ((sin x)/(sin (x−a)))dx |
∫ (dx/((sin x)^((14)/9) (cos x)^(4/9) )) |
![]() |
![]() |
Eeasy integral.... 𝛀 = ∫_(−∫_0 ^( ∞) e^( −x^( 2) ) dx) ^( ∫_0 ^( ∞) e^( −x^( 2) ) dx) sin^( 2) (t).ln^( 3) ( t + (√(1+t^( 2) )))dt −−−m.n−−− |
![]() |
𝛗=∫_0 ^( 1) (( ( tanh^( −1) (x))^2 )/((1+x )^( 2) )) dx = ? ≺ solution ≻ note : tanh^( −1) (x)=− (1/2) ln(((1−x)/(1+x))) 𝛗= (1/4)∫_0 ^( 1) (( ln^( 2) (((1−x)/(1+x)) ))/((1+x )^( 2) )) dx =^(((1−x)/(1+x)) = t) (1/8)∫_0 ^( 1) ln^( 2) (t )dt =(1/8_ ) { [t.ln^( 2) (t)]_0 ^( 1) −2∫_0 ^( 1) ln(t)dt} =− (1/4) ∫_0 ^( 1) ln(t)dt= (1/4) ◂ m.n ▶ |
(1) ∫^(π/2) _(π/3) ((1+sinx)/(cosx)) dx=? |
−−−− calculate: Φ = Σ_(n=0) ^( ∞) (( 1)/((2n+1 ).e^( 4n+2) )) = ? where ” e ” is euler number. ≺ solution ≻ Φ = Σ_(n=0) ^∞ (1/e^( 4n+2) ) ∫_0 ^( 1) x^( 2n) dx = (1/e^( 2) ) ∫_0 ^( 1) Σ_(n=0) ^∞ ((( x^2 )/e^( 4) ) )^( n) dx = (1/e^( 2) ) ∫_0 ^( 1) (( 1)/(1− ((x/e^( 2) ) )^( 2) )) dx=(1/(2e^( 2) )) ∫_0 ^( 1) (1/(1−(x/e^( 2) ))) +(1/(1+(x/e^( 2) )))dx = (1/2) ln ( ((1+(1/e^( 2) ))/(1−(1/e^( 2) ))) ) = tanh^( −1) ((( 1)/e^( 2) ) ) ∴ Φ = coth^( −1) ( e^( 2) ) ■ m.n |
Ω = ∫_0 ^( 1) (( x.tanh^( −1) (x))/((1+x)^( 2) ))dx= (1/(24)) (π^( 2) −6) |
![]() |
Ψ = ∫_0 ^( 1) (( ln( 1+ x − x^( 2) ))/x)dx = ? |
∫ ((log (cosx + (√(cos2x))) )/(1−cos^2 x ))dx |
∫cos2xlog(1+tanx)dx |