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By Differentiating from first principles, find the gradient of the curve f(x) = x^2 at the point where x = 2

This qustion can be solved easily using the gradient formular, m = ∆y/∆x, and some simple algrebra. The gradient at the point x = 2 is calculated by find the gradient of a tangent at x = 2. To find this we i...
HF
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When is the subjunctive used in Spanish, and how is it conjugated?

The subjunctive is one of the most important new aspects of Spanish grammar learnt at A Level. It is actually far more simple than people make it out to be, and Spanish speakers use it all the time! It isn't...
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Answered by Nicholas C. • Spanish tutor
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Determine Ka of a monohydric acid if the pH=2 and the initial concentration is 0.445 mol/L!

First of all we have to determine how much of the acid is dissociated, which we can do by determining the concentration of Hydrogen ions. We can work that out from the pH. pH=2, which means [H + ]=10 -2 mol/...
PN
Answered by Petra N. • Chemistry tutor
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Let f(x) = 2x^3 + x^2 - 5x + c. Given that f(1) = 0 find the values of c.

In order to solve this question we simply must substitute x=1 into f(x). But what is f(x)? What does it actually mean to make a subsitution? f(x) has a fancy name attached to it called a function . It is ess...
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Answered by Michael L. • Maths tutor
10914 Views

What happens to reactivity as you go down group 1 in the periodic table?

As you go down the group, what changes? The number of shells. As you go down the group, what doesn't change? The number of electrons in the outer shell - it is always one. For group 1, they become reactive w...
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Answered by Divya V. • Chemistry tutor
10864 Views