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 212635 by Nadirhashim last updated on 19/Oct/24

  m≤∫_1 ^3 ((1 )/(√(2x^2 +7 ))) .dx≤k find  the value of the constant    m and k

m3112x2+7.dxkfindthevalueoftheconstantmandk

Commented by Ghisom last updated on 19/Oct/24

this is a strange question  ∫_1 ^3 (dx/( (√(2x^2 +7))))=(√2)ln (1+2(√2))−((√2)/2)ln 7  ⇒ m=k=(√2)ln (1+2(√2))−((√2)/2)ln 7  if m, k ∈Z ⇒ m=0, k=1

thisisastrangequestion31dx2x2+7=2ln(1+22)22ln7m=k=2ln(1+22)22ln7ifm,kZm=0,k=1

Answered by mehdee7396 last updated on 19/Oct/24

f(x)=(1/( (√(2x^2 +7))))  ⇒ f′(x)=((−2x)/( (2x^2 +7)(√(2x^2 +7))))<0⇒f↘  f(1)=(1/3)=max    &   f(3)=(1/5)=min  ⇒(2/5)<∫_1 ^3 (1/( (√(2x^2 +7))))dx<(2/3)  ⇒m=(2/5)  &  k=(2/3)

f(x)=12x2+7f(x)=2x(2x2+7)2x2+7<0ff(1)=13=max&f(3)=15=min25<1312x2+7dx<23m=25&k=23

Commented by Ghisom last updated on 19/Oct/24

this is also a strange answer  why not  m=((13)/(25))∧k=((53)/(100))  or  m=((163297)/(312500))∧k=((1045101)/(2000000))

thisisalsoastrangeanswerwhynotm=1325k=53100orm=163297312500k=10451012000000

Commented by mehdee7396 last updated on 20/Oct/24

Commented by Ghisom last updated on 20/Oct/24

but this is a special definition, never  heard of it before. it makes sense for an  integral we cannot solve exactly.

butthisisaspecialdefinition,neverheardofitbefore.itmakessenseforanintegralwecannotsolveexactly.

Terms of Service

Privacy Policy

Contact: info@tinkutara.com