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# Maths integration. Need help! watch

1. Here is a link to the problem:
http://postimg.org/image/lj5hd20kj/
I don't know what dy is!
I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
surely the dy of y^1/2 is
2/3 y ^3/2
because when you differentiate you - 1 from the power, so working in reverse order.
y^1/2+1 = y^3/2
so what times' by 3/2 to make 1? 2/3, surely?
but I keep getting wrong answer?
I'm getting incredibly frustrated. have posted on here 3 times now with no help.
Anyone?
2. (Original post by Danny.L)
Here is a link to the problem:
http://postimg.org/image/lj5hd20kj/
I don't know what dy is!
I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
surely the dy of y^1/2 is
2/3 y ^3/2
because when you differentiate you - 1 from the power, so working in reverse order.
y^1/2+1 = y^3/2
so what times' by 3/2 to make 1? 2/3, surely?
but I keep getting wrong answer?
I'm getting incredibly frustrated. have posted on here 3 times now with no help.
Anyone?
what board are you doing?
3. (Original post by Danny.L)
Here is a link to the problem:
http://postimg.org/image/lj5hd20kj/
I don't know what dy is!
I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
surely the dy of y^1/2 is
2/3 y ^3/2
because when you differentiate you - 1 from the power, so working in reverse order.
y^1/2+1 = y^3/2
so what times' by 3/2 to make 1? 2/3, surely?
but I keep getting wrong answer?
I'm getting incredibly frustrated. have posted on here 3 times now with no help.
Anyone?

yes ∫y^(1/2) dy = (2/3)y^(3/2) +c

integration is the opposite of differentiation so just add one to the power then divide by it. But don't forget the constant +c because if you differentiated 3x+2 for example you would get 3... the 2 'disappears' so doing the reverse you write +c on the end to represent the unknown number.
4. (Original post by Danny.L)
Here is a link to the problem:
http://postimg.org/image/lj5hd20kj/
I don't know what dy is!
I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
surely the dy of y^1/2 is
2/3 y ^3/2
because when you differentiate you - 1 from the power, so working in reverse order.
y^1/2+1 = y^3/2
so what times' by 3/2 to make 1? 2/3, surely?
but I keep getting wrong answer?
I'm getting incredibly frustrated. have posted on here 3 times now with no help.
Anyone?
What answer do you get for the area in the first question?
5. (Original post by davros)
What answer do you get for the area in the first question?
the answer is 36 but I have no idea how to get it!
6. (Original post by Danny.L)
the answer is 36 but I have no idea how to get it!
I must be going a bit mad then, because I get 16/3 for area A and hence 32/3 for the total area.
7. (Original post by davros)
I must be going a bit mad then, because I get 16/3 for area A and hence 32/3 for the total area.
(Original post by Danny.L)
the answer is 36 but I have no idea how to get it!
It looks like the answer box is for a mixed fraction, but davros is definitely right.
8. (Original post by buxtonarmy)
Area A is 8/3 and hence 16/3 for the total area?
No

I think you might have found the area under the curve
9. (Original post by buxtonarmy)
Area A is 8/3 and hence 16/3 for the total area?

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