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Kieran, Jermaine and Chris play football. Kieran has scored 8 more goals than Chris. Jermaine has scored 5 more goals than Kieran. Altogether they have scored 72 goals. How many goals did Jermaine score?

Find an equation that explains the problem. We can see how many goals the players have scored in comparison to each other. The person with the fewest goals is Chris. Let us say he score x goals. Then we can ...
DC
Answered by Daniel C. • Maths tutor
19398 Views

Find the gradient of the exponential curve y(x)=(9e^(7x))/(12e^(2x)) at x=2/5

According to the quotient rule, when y(x)=f(x)/g(x), y'(x)=(f'(x)g(x)-g'(x)f(x))/g(x) 2 f(x)=9e 7x f'(x)=63e 7x , g(x)=12e 2x g'(x)=24e 2x y'(x)=(63e 7x .12e 2x -24e 2x .9e 7x )/(12e 2x ) 2 y'(x)=(756e 9x -2...
CM
Answered by Connor M. • Maths tutor
3669 Views

Use the double angle formulae and the identity cos(A+B)≡cos(A)cos(B)−sin(A)sin(B) to obtain an expression for cos 3x in terms of cos x only

To answer, you need to know and be able to use your trigonometric formulae including the double angle formulae on data sheet. 1: cos(3x)=cos(2x+x) = cos(2x)cos(x) - sin(2x)sin(x) split the 3x into two terms,...
SH
Answered by Sam H. • Maths tutor
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(2x+3)/(x-4) - (2x-8)/(2x+1) = 1 Solve for x

Multiply out the denominator, take care to multiply both sides of the equation: (2x+3)(2x+1) - (2x-8)(x-4) = (2x+1)(x-4) Expand the brackets, pay attention the the signs when multiplying, expecially the nega...
LM
Answered by Lucy M. • Maths tutor
3857 Views

There are n sweets in a bag, 6 of which are red. The rest of the sweets are blue. Jen removes 1 sweet from the bag. Jen then takes another sweet from the bag. The probability that Hannah takes two red sweets is 1/3. Show that n²-n-90=0.

We know the total number of sweets is n, and that 6 are red. When Jen takes the first sweet, the probability of it being red is [number of red sweets] / [how many there are] = 6/n . For the second sweet, the...
AB
Answered by Amy B. • Maths tutor
5570 Views