Four less than the square of a number

Mathematics

1 answer:

matrenka [14]3 years ago

6 0

Answer: x² - 4

Four less than the square of a number

↓ ↓

(Take away 4) x²

Four less than the square of a number = x² - 4

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Suppose cos(x)= -1/3, where π/2 ≤ x ≤ π. What is the value of tan(2x). EDGE

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Step-by-step explanation:

We are given that:

$\displaystyle \cos x = -\frac{1}{3}\text{ where } \pi /2 \leq x \leq \pi$

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$\displaystyle \tan(2x)=\frac{2\sin x\cos x}{\cos^2 x-\sin^2 x}$

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