I Why Is the Integral Result 175/3 Instead of 45?

  • I
  • Thread starter Thread starter homeworkhelpls
  • Start date Start date
  • Tags Tags
    Area Curve
AI Thread Summary
The integral of y, expressed as (1/3)x^3 + 2x, evaluated from the upper limit of 5 to the lower limit of 2, yields a result of 45, not 175/3. The correct evaluation of 175/3 occurs if the lower limit is set at x=-2. Participants suspect a possible typo or calculation error by the question setter. Additionally, there is a notation clarification suggesting that (1/3)x^3 should be used to avoid confusion with 1/(3x^3). This discussion highlights the importance of precise notation in mathematical expressions.
homeworkhelpls
Messages
41
Reaction score
1
1675365471735.png

i integrated y to get (1/3x^3 + 2x) with upper limit 5 / lower limit 2 but got 45 not 175 / 3
 
Last edited by a moderator:
Mathematics news on Phys.org
homeworkhelpls said:
View attachment 321610
i integrated y to get (1/3x^3 + 2x) with upper limit 5 / lower limit 2 but got 45 not 175 / 3
Both Wolfram Alpha and I agree with you.
 
Reply
  • Like
Likes homeworkhelpls and topsquark
Me too!
 
Reply
  • Like
Likes homeworkhelpls
The integral would evaluate to 175/3 if the lower limit were x=-2. I suspect a silly typo or calculation slip by the question setter.
 
Last edited:
Reply
  • Informative
  • Like
Likes homeworkhelpls and PeroK
homeworkhelpls said:
View attachment 321610
i integrated y to get (1/3x^3 + 2x) with upper limit 5 / lower limit 2 but got 45 not 175 / 3
Just a notation tip. 1/3x^3 can be misread as 1/(3x^3) placing the x^3 in the denominator. To be precise, we can instead write (1/3)x^3 to ensure x^3 is in the numerator and not mistakenly placed in the denominator.
 

Thread 'Non-orthogonal bases'

Suppose ,instead of the usual x,y coordinate system with an I basis vector along the x -axis and a corresponding j basis vector along the y-axis we instead have a different pair of basis vectors ,call them e and f along their respective axes. I have seen that this is an important subject in maths My question is what physical applications does such a model apply to? I am asking here because I have devoted quite a lot of time in the past to understanding convectors and the dual...
View full post »

Thread 'Fermat's Last Theorem'

Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
View full post »

Thread 'What Exactly is Dirac’s Delta Function? - Insight'

Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
View full post »

Similar threads

B Integration from "Area Under Curve" Perspective: Explained
Replies
11
Views
2K
B Solving the Heart Curve Equation: 'y =
Replies
18
Views
4K
B Upper and Lower Bounds of Polynomials
Replies
8
Views
5K
MHB Quadratic equations ( solving for zeros/roots) trickey
Replies
1
Views
1K
MHB Why I Get X & Y Mixed Up When Plotting Graphs
Replies
3
Views
2K
MHB -7.64 Determine the following standard normal (z) curve areas:
Replies
1
Views
1K
MHB How Do You Solve This Complex Double Integral with Given Curves?
Replies
6
Views
2K
MHB Fixed point,, Jacobi- & Newton Method, Linear Systems
Replies
7
Views
2K
I Different Substitution for Solving an Integral
Replies
6
Views
2K
MHB How to Use Elliptic Curve Cryptography to Find Inverses and Points on the Curve?
Replies
2
Views
2K

Hot Threads

Recent Insights

Back
Top