My Math Forum  

Go Back   My Math Forum > College Math Forum > Calculus

Calculus Calculus Math Forum


Reply
 
LinkBack Thread Tools Display Modes
June 3rd, 2017, 06:07 AM   #1
Newbie
 
Joined: Jun 2017
From: England

Posts: 1
Thanks: 0

Point of intersection coordinates (Diff)

Hi, I'm revising for an upcoming calculus test and have a differentiation problem. A curve y=x^2 + x + 3 and line y = 2x + 5 are on a graph diagram (not to scale). I need to find the co ordinates for each two points of intersection on the graph.

I'm not sure whether I'd use the turning points method for maximum / minimum values? Or whether it's actually an integration problem?

With the turning point method would I first add both equations into one simultaneous equation 2x + 5 = x^2 + x + 3 differentiate that, rearrange and then factorise? Or rearrange, differentiate then factorise?

Thanks
Day3091 is offline  
 
June 3rd, 2017, 06:45 AM   #2
Math Team
 
skeeter's Avatar
 
Joined: Jul 2011
From: Texas

Posts: 3,101
Thanks: 1677

Quote:
A curve y=x^2 + x + 3 and line y = 2x + 5 are on a graph diagram (not to scale). I need to find the co ordinates for each two points of intersection on the graph.
if the intersection(s) of the two functions are all that is required, then calculus is unnecessary ... just set the two functions equal to each other and solve for $x$ ...

$x^2+x+3 = 2x+5$

$x^2-x-2=0$

$(x-2)(x+1)=0$

$x=2 \implies y = 9$

$x=-1 \implies y = 3$
skeeter is offline  
Reply

  My Math Forum > College Math Forum > Calculus

Tags
coordinates, diff, intersection, point



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Get coordinates of every point inside an ellipse and detect intersection of 2 ones. Ziya1995 Geometry 9 August 29th, 2014 06:04 AM
Calculate intersection point sososasa Algebra 3 March 21st, 2014 10:15 AM
Solving Diff Eqns using Euler's and Mid-point formulas daveollie Applied Math 0 December 5th, 2013 11:04 PM
Point of Intersection Phazon Algebra 2 May 9th, 2011 12:58 PM
calculating the point of self-intersection questioner1 Algebra 3 December 16th, 2009 11:41 AM





Copyright © 2019 My Math Forum. All rights reserved.