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What is the ontological argument and its features?

The Ontological Argument (OA) is related to the nature and essence of an object and this argument attempts to prove that God must exist by his very nature. Many philosophers formulate theories to support ...

Answered by Sophie F. • Philosophy and Ethics tutor

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There are n sweets in a bag, 6 of which are orange. If the probablility of eating 2 orange sweets from the bag, one after the other, is 1/3, show that n^2 - n - 90 = 0. State any assumptions made.

We are assuming that the sweets are selected at random. The question says that the sweets are eaten, so we are also assuming that they aren't put back into the bag. The total probability of selecting the ...

Answered by James B. • Maths tutor

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Give an example of a real-world system that would be described by a quadratic equation. Explain the significance of the two real roots, a repeated root, and undefined roots. Is there any significance to a positive or a negative answer in your example?

For a ball that has been thrown, it's height above the ground can be described by a quadratic equation of the time since it was thrown and gives a parabola.

The two real roots of the equation are t...

Answered by James B. • Maths tutor

4252 Views

How can i use completing the square to factorise and solve equations

This method will only work if your x term is divisible by 2. For example x² + 6x + 12.

You then use the halved x term (e.g. 3x) to complete the square. The beginning of your factorisat...

Answered by Natalie S. • Maths tutor

4677 Views

How does Haemoglobin work?

Haemoglobin is a protein made up of 4 sub-units. Each sub-unit has a molecule of un-oxygenated Iron. Oxygen covalently bonds to the Iron and is thereby carried by the blood as Oxy-haemoglobin. Oxy-haemogl...

Answered by Conor J. • Biology tutor

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