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Which of the following represents vector t = –8i + 6j in trigonometric form?

Which of the following represents vector t = –8i + 6j in trigonometric form?-example-1
User Salina
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2.8k points

2 Answers

1 vote

Answer:

yup it is the second option

Explanation:

User Jodian
by
3.8k points
4 votes

The vector is given to be:


t=-8i+6j

For a vector v given to be:


v=ai+bj

the trigonometric form is given to be:


v=|v|\langle\cos \theta,\sin \theta\rangle

where


|v|=\sqrt[]{a^2+b^2}

and


\theta=\tan ^(-1)(b)/(a)

Comparing this to our vector, we have:


\begin{gathered} a=-8 \\ b=6 \end{gathered}

Therefore,


\begin{gathered} |t|=\sqrt[]{(-8)^2+6^2}=\sqrt[]{64+36}=\sqrt[]{100} \\ |t|=10 \end{gathered}

and


\begin{gathered} \theta=\tan ^(-1)((6)/(-8))=_{}\tan ^(-1)(-(6)/(8))_{} \\ \theta=-36.87 \end{gathered}

Since the angle is negative, we can add 180° to the angle to get the positive angle. Therefore:


\theta=-36.87+180=143.13

Therefore, the vector in trigonometric form will be:


t=10\langle\cos 143.13,\sin 143.13\rangle

The correct option is the SECOND OPTION.

User Sk Saad Al Mahmud
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3.1k points