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Find the equation of the normal to the curve x^3 + 2(x^2)y = y^3 + 15 at the point (2, 1)

The first thing when seeing such a question is to find out what the question wants you to do and plan your method to do so.In this case, the question asks you to find the normal of a curv...

Answered by Kelvin L. • Maths tutor

3565 Views

Why does ionization energy increase across a period?

First of all, let's define ionization energy. Ionization energy is the energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms. The higher this energy is, the harder it is to remove t...

Answered by Amelia F. • Chemistry tutor

27044 Views

Expand (x-3)(x+7)

FOIL Method: F - First xx = x² O - Outside x7=7x I - Inside -3x=-3x L - Last -37= -21 Add all the results up to get the answer: x²+7x-3x-21 = x²

Answered by Martin L. • Maths tutor

7196 Views

Find the value of x: 2x^2 - 3x - 4 = 1

2x^2 - 3x - 4 = 1
To solve, we should bring all the terms to one side, and equate the equation to 0. To do this, we should subtract 1 from each side.
2x^2 - 3x - 4 - 1 = 1 - 12x^2 - 3x - 5 = 0

Answered by Prithvie S. • Maths tutor

3828 Views

Why does magnesium have a higher melting point than sodium?

Both sodium and magnesium have metallic bonding between atoms. Outer electrons become delocalised and float freely between the positive ions. The positive ions attract the negatively charged electrons so ...

Answered by Suzie C. • Chemistry tutor

39501 Views