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The curve C has equation y = (x^2 -4x - 2)^2. Point P lies on C and has coordinates (3,N). Find: a) the value of N. b) the equation of the tangent to C at the point P, in the form y=mx+c where m and c are constants to be found. c) determine d^2y/dx^2.

a) Sub x=3 into the given equation. N is found to be 25.b) Finding dy/dx gives me, as the first differential is the gradient.First differentiate the power and then multiply the differential of the express...

Answered by Tom A. • Maths tutor

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Explain why a skill may be classified as open?

An open skill is one which is externally paced and is controlled by the environment around the performer. Movements must be adapted to this change in the environment. For example, a hockey midfielder look...

Answered by • Physical Education tutor

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Two masses A and B, 2kg and 4kg respectively, are connected by a light inextensible string and passed over a smooth pulley. The system is held at rest, then released. Find the acceleration of the system and hence, find the tension in the string.

First we draw a diagram of this system (on whiteboard). Remember to label diagram correctly - the tension on both sides act towards each other.
Since B is a larger mass, we know that mass A will mov...

Answered by • Maths tutor

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How does free radical substitution work?

(This explanation would make use of diagrams on a whiteboard)It is useful to break this down into three steps: 1- the initiation step. Let's take the reaction between Cl₂ and CH₄.

Answered by Tom H. • Chemistry tutor

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What is the point of a derivative?

A derivative is a rate of change. For example, let y equal some function of x. Then the derivative of y with respect to x is asking how much y changes with respect to x. We can show this for any x and if ...

Answered by • Maths tutor

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