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Jodie buys 12 cans of cola. There are 330 ml of cola in each can. Rob buys 4 bottles of cola. There is 1 litre of cola in each bottle. Rob buys more cola than Jodie. How much more?

The answer is: (4X1000)-(12X330)= 40, ao 40 ml more. You may wonder why 1 litre is 1000, as 1 litre of cola= 1000 ml of cola so we have to convert 1 L to 1000ml in the anwer. Rob buys more cola than Jodie me...
MK
Answered by Michelle K. • Maths tutor
3888 Views

Calculate the volume of revolution generated by the function, f(x) = (3^x)√x, for the domain x = [0, 1]

First we recall the general formula for the volume of revolution: V = π ∫ [f(x)]² dx Substituting our function, this gives: V = π ∫₀¹ (3^x)² x dx We could write (3^x)² as 3^(2x), or we could notice that this...
RH
Answered by Reece H. • Maths tutor
6405 Views

How to I factorise a quadratic equation?

I think the best way to show how to do this is with an example "Factorise 6x 2 + 7x - 3" Looking at that expression, we can't factorise it straight away, so we'll have to rewrite it in a way that a...
DB
Answered by Daisy B. • Maths tutor
6185 Views

Express Cosx-3Sinx in form Rcos(x+a) and show that cosx-3sinx=4 has no solution MEI OCR June 2016 C4

Cosx-3sinx =R(CosxCosa-SinxSina) 1=Rcosa R^2=1^2+3^2 r=(10)^0.5=(approx)3.16 a=1.249 3.16Cos(x+1.249)=4 has no solution as 4<3.16 so as cos(theta) has maximum value of 1, there are no solutions
JP
Answered by Jakub P. • Maths tutor
5749 Views

How do you find the area of a semi circle with a radius of 7cm?

You should remember that a semi circle is the same as half a circle, therefore the area must be half as well! The formula for the area of a circle is pi r^2. If we use this, the area of our circle = pi x (7^...
CJ
Answered by Cindiya J. • Maths tutor
13736 Views