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# Integration help needed C2 watch

1. My question;

For the curve and straight lines, find their points of intersection, draw a sketch on the same axes and find the area of segment cut off from each curve by the corresponding straight line.

a)

sOLUTION
points of coordinates (-1,0) (3,4)

Area required = Area of trianagle -
=
=
break into two

bring it together
area required =

the book says the answer is
i have attached my sketch
2. (Original post by bigmansouf)
My question;

For the curve and straight lines, find their points of intersection, draw a sketch on the same axes and find the area of segment cut off from each curve by the corresponding straight line.

a)

sOLUTION
points of coordinates (-1,0) (3,4)

Area required = Area of trianagle -
=
=
break into two

bring it together
area required =

the book says the answer is
i have attached my sketch
I also got 32/3 by integrating x+1 -(x+1)(x-2) between -1 and 3
3. (Original post by bigmansouf)
My question;

For the curve and straight lines, find their points of intersection, draw a sketch on the same axes and find the area of segment cut off from each curve by the corresponding straight line.

a)

sOLUTION
points of coordinates (-1,0) (3,4)

Area required = Area of trianagle -
=
=
break into two

bring it together
area required =

the book says the answer is
i have attached my sketch
what area are you finding?
4. (Original post by TeeEm)
what area are you finding?
i assume that the area i am asked to find is the one coloured in the pic

thanks for the help
5. (Original post by bigmansouf)
i assume that the area i am asked to find is the one coloured in the pic

thanks for the help
I think it is that plus the bit under the x axis, bounded by the curve.
6. (Original post by TeeEm)
I think it is that plus the bit under the x axis, bounded by the curve.
in that sense would you say that my method was wrong
7. (Original post by TeeEm)
I also got 32/3 by integrating x+1 -(x+1)(x-2) between -1 and 3
thanks found this answer it seems that i was wrong
i was not looking for the right area

i think if it was suppose to be the area that i thought it would have said the curve, straight line and x-axis

thank i understand where i was going wrong
8. (Original post by bigmansouf)
in that sense would you say that my method was wrong
no
you just need to add the bit under

integrate the curve between -1 and 2
turn the answer positive and add it to 37/6 and see what you get
(I did it differently)
9. (Original post by TeeEm)
no
you just need to add the bit under

integrate the curve between -1 and 2
turn the answer positive and add it to 37/6 and see what you get
(I did it differently)
your way would be the best and simplest method but i decide to apply the alternative of using areas of shapes and then subtracting it i thought it would be easier
in most cases it is but not in this one
10. (Original post by bigmansouf)
your way would be the best and simplest method but i decide to apply the alternative of using areas of shapes and then subtracting it i thought it would be easier
in most cases it is but not in this one

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