The Student Room Group
Uni students - Complete our survey >>
Uni students - Complete our survey >>
Uni students - Complete our survey >>

why don't we include the c when finding the area under the curve

as the title says
Reply 1
Avatar for srbryant
srbryant
8
um im confused i dont understand your question
you could write it in, but look what happens...

[...... + c ] - [...... + c ]
Reply 3
Avatar for NotGay
NotGay
4
Original post by interlanken-fall
as the title says

my men

you can include the c, but you will have the same c when you minus. c minus c is zero HAHA SO WE DONT NEED C!
Original post by srbryant
um im confused i dont understand your question

when we integrate any equation and we add c as a constant, why don't we add it when we try to find the area
Reply 5
Avatar for Notnek
Notnek
21
Original post by interlanken-fall
as the title says

Simple example with me including the +c

Find the area under the line y = x from x = 1 to x = 2:

∫12x dx=[x22+C]12=(2+C)−(12+C)=32\displaystyle \int_1^2 x \ dx = \left[\frac{x^2}{2} + C\right]^2_1 = (2+C) - \left(\frac{1}{2}+C \right) = \frac{3}{2}

Can you see why including the +C is unnecessary?

EDIT: Too late even at 23:20 on a Friday night :cry2:
(edited 3 years ago)
Original post by Notnek
Simple example with me including the +c

Find the area under the line y = x from x = 1 to x = 2:

∫12x dx=[x22+C]12=(2+C)−(12+C)=32\displaystyle \int_1^2 x \ dx = \left[\frac{x^2}{2} + C\right]^2_1 = (2+C) - \left(\frac{1}{2}+C \right) = \frac{3}{2}

Can you see why including the +C is unnecessary?

EDIT: Too late even at 23:20 on a Friday night :cry2:

ohhhhhhhhhhhhhh they cancel out thank you!!
sorry I have exams after half term so cramping everything in going to bed after 1 more question good night!!
Reply 7
Avatar for Notnek
Notnek
21
Original post by interlanken-fall
ohhhhhhhhhhhhhh they cancel out thank you!!
sorry I have exams after half term so cramping everything in going to bed after 1 more question good night!!

I meant that my reply was too late since others had already answered. It's never too late to be doing maths questions :dumbells:
When you're integrating w/o limits/indefinite integrals, you have to include a constant (+C) at the end because it's not a single function like definite integrals. Also, as bear stated, the +c will cancel out anyway so need for it.
Reply 9
Avatar for srbryant
srbryant
8
Original post by interlanken-fall
when we integrate any equation and we add c as a constant, why don't we add it when we try to find the area


oh now it make more sense
C’s cancel out

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you