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Two ordinary fair dice are rolled. Work out the probability that both land on a value less than 4.

The probability of an event= Number of ways an event can occur/ Total number of possible outcomesBoth dices land on values less than 4. This means they both can be 1,2 or 3. Therefore, number of ways the eve...
GS
Answered by George S. • Maths tutor
7148 Views

Explain the trend of first ionisation energy down a group.

The first ionisation energy is the energy required to remove one electron from an atom. Down a group, there are more electron shells surrounding the nucleus, which results in a greater shielding from the nuc...
RW
Answered by Rachael W. • Chemistry tutor
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g(x) = ( x / (x+3) ) + ( 3(2x+1) / (x^2 + x - 6) ). Show that this can be simplified to: g(x) = (x+1) / (x-2).

Step 1: The denominator of the right-hand fraction is quadratic, so we can factorise this to (x+3)(x-2). This looks similar to the denominator of the left-hand fraction, suggesting we can combine the two. St...
AS
Answered by Amar S. • Maths tutor
6240 Views

Give TWO similarities in the movement of substances by diffusion and by osmosis.

(Movement) down a gradient / from high concentration to low concentration; 2. Passive / not active processes; OR Do not use energy from respiration / from ATP / from metabolism; OR Use energy from the soluti...
MS
Answered by Murtaza S. • Biology tutor
12201 Views

A curve has the equation: x^2(4+y) - 2y^2 = 0 Find an expression for dy/dx in terms of x and y.

First of all expand the brackets in the equation. Then you can differentiate each term with respect to x. As one of the terms will be a product of x and y the product rule must be used to find the differenti...
CM
Answered by Carlotta M. • Maths tutor
4552 Views