Question and Answers Forum

All Questions      Topic List

Integration Questions

Previous in All Question      Next in All Question      

Previous in Integration      Next in Integration      

Question Number 63089 by mathmax by abdo last updated on 28/Jun/19

find the value of ∫_0 ^(π/2)   (dx/(1+(tanx)^(√2) )) .

findthevalueof0π2dx1+(tanx)2.

Commented by edafe ovwie last updated on 29/Jun/19

using  ∫_b ^a f(x)dx=∫_b ^a f(a+b−x)dx  let  𝛀=∫_0 ^(π/2) (1/(1+(tanx)^(√2) ))dx.....1  𝛀=∫_0 ^(π/2) (1/(1+(tan((𝛑/2)−x))^(√2) ))dx  tan((π/2)−x)=cotx=(1/(tanx))  𝛀=∫_0 ^(π/2) (1/(1+(cotx)^(√2) ))dx  𝛀=∫_0 ^(π/2) (((tanx)^(√x) )/(1+(tanx)^(√2) ))dx...2  add 1 and 2  2𝛀=∫_0 ^(π/2) 1dx  2Ω=(π/2)  Ω=(π/4)  ∫_0 ^(π/2) (1/(1+(tanx)^(√2) ))dx=(π/4)

usingbaf(x)dx=baf(a+bx)dxletMissing \left or extra \rightMissing \left or extra \righttan(π2x)=cotx=1tanxMissing \left or extra \rightMissing \left or extra \rightadd1and22Ω=0π21dx2Ω=π2Ω=π4Missing \left or extra \right

Commented by mathmax by abdo last updated on 29/Jun/19

thank you sir .

thankyousir.

Commented by mathmax by abdo last updated on 03/Jul/19

let A =∫_0 ^(π/2)    (dx/(1+(tanx)^(√2) ))  changement x =(π/2)−t give  A =−∫_0 ^(π/2)    ((−dt)/(1+ ((1/(tant)))^(√2) )) = ∫_0 ^(π/2)     (((tant)^(√2) )/(1+(tant)^(√2) )) dt =∫_0 ^(π/2)  ((1+(tant)^(√2) −1)/(1+(tant)^(√2) ))dt  =(π/2) −A ⇒ 2A =(π/2) ⇒ A =(π/4) .

letA=0π2dx1+(tanx)2changementx=π2tgiveA=0π2dt1+(1tant)2=0π2(tant)21+(tant)2dt=0π21+(tant)211+(tant)2dt=π2A2A=π2A=π4.

Terms of Service

Privacy Policy

Contact: info@tinkutara.com