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I am utterly confused with this question and its driving me crazy that I cant figure it out

I am utterly confused with this question and its driving me crazy that I cant figure-example-1

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We are given two vectors in magnitude , angle form , and want to find the component form of them.

We recall that the x-component of a vector is given by the cosine projection of its magnitude, while the y-component is given by the sine projection:

Then in general terms:

x-component = |V| cos (angle)

y-component = |V| sin(angle)

where |V| representes the magnitude of the given vector.

So for our cases:

Case a)

the magnitude is 16 and the angle is 225 degrees, therefore:

x-component = 16 * cos(225) = -11.3137...

y-component - 16 * sin(225) = -11.3137....

this is telling us that the vector is on the third quadrant and corresponds to equal x and y components. So we could have expressed them in exact form using the fact that the sin and cos of that angle can be expressed by square root of 2 divided by 2.

So if they want the EXACT value, you write : -16 * root(2) / 2 = - 8 root(2)for each one.

Case b):

12 is the magnitude and 63 degrees the angle. Then:

x-component = 12 * cos(63) = 5.4479

y-component = 12 * sin(63) = 10.6921

So this vector is on the first quadrant, and the angloe is not a special angle so we don't have an easy square root expression for the sine and cosine.

User Roderick Bant
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