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A cuboid of height 5 cm has a base of side 'a' cm. The longest diagonal of the cuboid is 'L' cm. Show that 'a' = SQRT[ (L^2 - 25)/2]

A cuboid is made of squares and rectangles, with the diagonal 'L' connecting opposite corners of the 2 square faces. As the cuboids corners are all right angles, all the diagonals form right angled triang...

Answered by Joshua P. • Maths tutor

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How do I simplify (1 / [1 + cos(x) ] ) + (1 / [1 - cos(x) ] )?

In order to add the fractions together, we must have a common denominator of the fractions. The simplest way to do this is to make the denominators of the equations the product of the original two denomni...

Answered by Simon C. • Maths tutor

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A curve has the equation: x^4 + 2x -xy - y^3 - 10=0. Find dy/dx in terms of x and y.

We need to differentiate all values with respect to x. Therefore for the first two terms, multiply by the power and then subtract 1 from the original power. Therefore 4(x^4-1) + (2)(2x^2-1

Answered by John G. • Maths tutor

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A conical vase of base radius 5cm and height 20cm is filled with 200ml of water, how high is the water level? Give your answer to 3 significant figures.

Answer: 2.96 cm

Equations used: Volume of a cone = (base area x height) / 3 ; Base Area = pi x radius²

Volume of whole vase = (pi x 5² x 20)/3 = 523.6 cm³

Answered by Ian C. • Maths tutor

2964 Views

A curve has equation y = e^x + 10sin(4x), find the value of the second derivative of this equation at the point x = pi/4.

Firstly, differentiate y with respect to x once to obtain the equation dy/dx = e^x + 40cos(4x). Then differentiate this resultant expression, with respect to x, to acquire a solution for (d^2)y/d(x^2) = e...

Answered by Joe I. • Maths tutor

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