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Do the points (4, π/4) and (-4, -π/4) represent the same point?

a. Yes, they represent the same point.
b. No, they represent different points.
c. Not enough information to determine.
d. They represent the same point in polar coordinates but not in Cartesian coordinates.

User Schenz
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1 Answer

1 vote

Final answer:

The points (4, π/4) and (-4, -π/4) represent the same location in polar coordinates but are different points in Cartesian coordinates. Option d is correct.

Step-by-step explanation:

The points (4, π/4) and (-4, -π/4) represent different points in the Cartesian coordinate system but the same point in polar coordinates. In polar coordinates, a negative radius can be understood as reversing the direction from the origin, and an angle with a negative value indicates rotation in the opposite direction (clockwise).

Therefore, if you consider a point at (r, θ) in polar coordinates and then a point at (-r, -θ), they will end up being at the same location after accounting for the direction reversal given by the negative radius and the angle's direction.

To be clearer, the point (4, π/4) in polar coordinates converts to a Cartesian point with positive x and y coordinates. The point (-4, -π/4) suggests a movement in the reverse direction both radially and angularly, ending up at the same Cartesian coordinates as the point (4, π/4). So answer option d is correct.

User Daniel Vargas
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