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Why do you differentiate in optimisation questions?

When you differentiate a function it is giving you the rate of change of that function for different values of x. After subituting in, if it is positive it tells us that the graph is increasing, if it is neg...
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Answered by Simon A. • Maths tutor
5191 Views

In terms of the structure and boiling point of graphite, explain why the melting point is high

Each carbon atom in graphite is bonded to three other carbon atoms. These carbon atoms are linked by covalent bonds - which are very strong. Graphite is arranged in sheet like structures and between each lay...
TM
Answered by Tinashe M. • Chemistry tutor
50989 Views

What happens to the rate of an enzyme-catalysed reaction when temperature increases? And when pH changes?

As temperature increases, the molecules involved in the reaction gain kinetic energy, increasing the chances of collision between the substrate molecules and the active sites of the enzymes, a step that is n...
MD
Answered by Maria D. • Biology tutor
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The lamp has an efficiency of 20%. Explain what this means.

20% efficiency means that 20% of the electrical energy going into the lamp is transfered to light, and 80% of the energy is lost/wasted.
BP
Answered by Bryce P. • Physics tutor
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f(x)=2x^3-7x^2+4x+4, prove that (x-2) is a factor and factorise f(x) completely

if (X-2) is a factor, f(2)=0 2 2^3-7 2^2+4*2+4= 16-28+8+4=0 therefore (x-2) is a factor. 2x^3-7x^2+4x+4=(x-2)(2x^2-3x-2)=(x-2)(2x+1)(x-2)
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Answered by Bryce P. • Maths tutor
5274 Views