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Prove that 1 + tan^2 x = sec^2 x

We know that tan x = sin x/cos x and so tan²x = sin²x/cos²x. We also know that sin²x + cos²x = 1 because this is a Pythagorean identity. We can rewri...

Answered by Eleanor F. • Maths tutor

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Integrate 2x^2 + 4

When we integrate, we raise the power by one and divide the term by the new power. So let's break the question down term by term. When integrating 2x² we raise the power by 1 to get 2x³

Answered by Eleanor F. • Maths tutor

5593 Views

In a science experiment a substance is decaying exponentially. Its mass, M grams, at time t minutes is given by M=300e^(-0.05t). Find the time taken for the mass to decrease to half of its original value.

Firstly, calculate the initial value of of M, by substituting t = 0 into the equation M=300e^-0.05tInitially, M₀= 300e⁰=300 x 1 = 300When the substance mass has decreased t...

Answered by Bony R. • Maths tutor

7997 Views

What is the difference between 'le, la, les' and 'un, une, des'?

'le, la , les' are called definite articles or articles définis and they are used when speaking of something specific or that has previously been mentioned. These article...

Answered by Carolina F. • French tutor

15547 Views

Consider reasons why turnout may differ significantly between different constituencies at general elections to the Westminster Parliament.

A key factor affecting turnout levels between consistencies stems from the majoritarian 'First Past The Post' electoral system that is employed in general elections. The 'winner takes all' nature of the F...

Answered by Greg R. • Government and Politics tutor

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