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Find the coefficient of x^4 in the expansion of: x(2x^2 - 3x + 1)(3x^2 + x - 4)

Only the terms which will form the x⁴ term need to be considered:x * 2x² * x + x * -3x * 3x² = -7x⁴Therefore the answer is -7.

Answered by Finn H. • Maths tutor

4844 Views

An object of mass 3kg is held at rest on a rough plane. The plane is inclined at 30º to the horizontal and has a coefficient of friction of 0.2. The object is released, what acceleration does the object move with?

We need to use Newtons law F=ma going down the slope.
We can see that the only forces acting in this direction are the component of the weight and friction, so we have that: F = Wsin30 - μR = 3a

Answered by Asha D. • Maths tutor

3529 Views

Describe how a stationary wave is formed at a boundary?

A stationary wave is a wave formed by the superposition of two progressive waves. These waves must have equal amplitude frequency and speed. They must also be travelling in opposite directions. When a wav...

Answered by Oliver E. • Physics tutor

5857 Views

Describe how action potentials are initiated and transmitted within a neurone, mentioning the appropriate ions and types of ion channels

A stimulus causes a small influx of sodium ions into the cell, leading the cell to become more depolarised or more positive. If this reaches the threshold potential, of about -55 mV, then it will initiate...

Answered by Roxanne M. • Biology tutor

2923 Views

Describe that lock and key hypothesis

Enzymes are biological catalysts, which means that they increase the rate of a specific reaction by lowing the required activation energy.
The lock and key hypothesis explains how the substrate (key)...

Answered by William W. • Biology tutor

7851 Views