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Topic : Multiple Representations of points

PLEASE HELP ME, am having a hard time with these questions

Topic : Multiple Representations of points PLEASE HELP ME, am having a hard time with-example-1

2 Answers

3 votes

Answer:

See below directions.

Explanation:

The condition
-2\pi<\theta<2\pi means you can get to the point by rotating no more than one revolution in either the positive or negative direction.

See the attached image to see the point
\left(3,\,-(3\pi)/(4)\right). Think about how you get to that point: start at the origin, go right (along the positive x-axis) 3 units, then turn in the negative direction (to your right!) through an angle of
(3\pi)/(4).

Now, go again, starting at the origin, only this time, go 3 units right, then turn through an angle of
-(3\pi)/(4)+2\pi=(5\pi)/(4). In other words, you turn one whole revolution in addition to the
-(3\pi)/(4) angle. Your point can now be described by
\left(3,\,(5\pi)/(4)\right).

Another description can be found by rotating in the opposite direction, so an angle of
(3\pi)/(4) and backing up 3 units -- specify a "radius" of -3. The point is then
\left(-3,\,(3\pi)/(4)\right).

You can also try subtracting one revolution
(2\pi) from the angle, but be careful not to let the angle go outside the interval
-2\pi<\theta<2\pi.

The changes you can try are:

add
2\pi to the angle, leave r alone

subtract
2\pi to the angle, leave r alone

add/subtract
\pi (half a revolution) to the angle, make r the opposite.

Topic : Multiple Representations of points PLEASE HELP ME, am having a hard time with-example-1
User Nishant Bhardwaz
by
4.5k points
3 votes

Answer:

Hmm, want piña colada and Jar Jar Binks cookies? just go to India.

User Sanilunlu
by
4.4k points