maths question help thanks (1 Viewer)

youngsky

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3) i.
Solve y = x^2 - 3x and y = -x^2 + x +6 simultaneously (equate them to each other)

2x^2 - 4x - 6 = 0
x^2 - 2x - 3 = 0
(x-3)(x+1) = 0
x = 3, -1
sub these values into either equation and you'll get the y values for P and Q

ii. Area between 2 curves, A = integral of TOP curve MINUS BOTTOM curve, the limits are the x-values of P and Q
 

Drongoski

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Q4: y=9-x^2 and y = 6-2x

Where they intersect: 9-x^2 = 6-2x ==>x^2-2x-3 = 0 ==> (x-3)(x+1) = 0 ==> x=-1 and x=3



You can work this out.
 
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guys whats the answer to 3.11 then is it 4 or -4 not too sure if there correct can some1 helpme out plz?
 

fatduckling

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Here is question 3 worked solutions
I think I may have done some simple silly mistakes, correct me if i have.
Please PM me if you need more help.

In the attatchments, the first file is 3ii and the 2nd one is 3i.
Here is question 4
 

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