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Given that (cos(x)^2 + 4 sin(x)^2)/(1-sin(x)^2) = 7, show that tan(x)^2 = 3/2

First, we use 1 - sin(x)^2 = cos(x)^2 and get:(LHS) (cos(x)^2 + 4 sin(x)^2)/(1-sin(x)^2)= (cos(x)^2 + 4 sin(x)^2)/cos(x)^2= 1 + 4 (sin(x)/cos(x))^2= 1 + 4 tan(x)^2Now we know that the left hand side is eq...

Answered by Bogdan-Adrian M. • Maths tutor

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The surface run-off of nitrate from agricultural fertiliser into freshwater ponds and lakes can cause the death of the fish. Explain how this happens.

This question crops up a lot and may be up to a five mark question, if you learn the key points and terms you can be confident of getting all the marks you can here!

First of all,

Answered by Sarah M. • Biology tutor

5463 Views

When do I need to put an accent (pronunciation rules)?

Spanish is great because it is a language which is completely phonetic, which means it is read exactly how it is written and always follows certain rules. One of those rules is about stress. All multi-...

Answered by Sebastian B. • Spanish tutor

4606 Views

What does a negative velocity mean?

To understand this question, it is important to know that velocity has both a direction and a magnitude. The magnitude can be expressed by the unit m/s, however the direction is expressed by a vector. ...

Answered by Thomas D. • Physics tutor

34517 Views

Why does a salt not conduct electricity in its solid state?

In order to conduct electricity, charged particles must be available and these charged particles must have the possibily to move around freely. Salts consist of ions: charged particles. In the solid st...

Answered by Thomas D. • Chemistry tutor

35584 Views