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Sketch y = 9x – 4x^3, showing where the curve crosses the x axis.

First you should look at the equation and try and get a sense of the general shape of the graph. The highest power in here is a 3, so this is a cubic graph. The coefficient (number in front of the x^3) is a ...
AE
Answered by Anais E. • Maths tutor
6136 Views

Solve (x^2 - 4)/(2x+4)

The common mistake the students make is to simplify the fraction before factorising numerator and denominator. Here, we need to see that the numerator: x^2 - 4 is a difference between squares , i.e. A^2 - B^...
MM
Answered by Martina M. • Maths tutor
4488 Views

A student of mass m=50kg runs an experiment. He throws a ball of mass m = 400g from a height h = 20m. What will be the speed of the ball he records just before it touches the ground?

First, we need to see what the important information in this problem is: the mass of the student is irrelevant as the problem focusses on the ball. So we now know that the important information is: m = 400g ...
MM
Answered by Martina M. • Physics tutor
2445 Views

“Mao's ideology was the primary cause for the failure of the Great Leap Forward of 1958 to 1962.” Assess the validity of this view.

Getting started: This question is asking us to assess the validity of a particular view which means that we need to relate the interpretation to the evidence that we have, and assess how valid/accurate this ...
JF
Answered by Jacob F. • History tutor
3503 Views

You are given a clear solution that is either an alkene or an alkane. Describe a test using bromine water that you could use to determine whether it is an alkene or alkane solution.

1 mark : Indication that the solution and bromine water should be mixed together1 mark : Indicating that the bromine water will de-colourise / go colourless if the solution contains an alkeneOR 1 mark awarde...
NH
Answered by Noah H. • Chemistry tutor
2743 Views