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2 years ago

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Mathematics

1 answer:

vovikov84 [41]2 years ago

3 0

Answer:

x = (+ - ) 9

Step-by-step explanation:

x^2 = 81

u know how u can sometimes cancel something out by doing the opposite.

This is one of those times as well. the opposite of ^2 = square root.

so if we take the square root of both sides, this will cancel out the^2 on the left side.

sqrt (x^2) = sqrt(81)

x = (+-) 9.....thats a positive and a negative sign...because the sqrt of 81 is both 9 and -9.

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Step-by-step explanation:

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where, $r=\sqrt{a^2+b^2}$ and $\tan \theta=\dfrac{b}{a}$ , $\theta$ is called the argument of z, $0\leq \theta\leq 2\pi$ .

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$\theta=2\pi -\dfrac{\pi}{2}$ $[\because \text{In 4th quadrant }\theta=2\pi-\theta]$

$\theta=\dfrac{3\pi}{2}$

So, the trigonometric form is

$z=5\left(\cos \left(\dfrac{3\pi}{2}\right)+i\sin \left(\dfrac{3\pi}{2}\right)\right)$

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