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Here we are, chapter four, problem number six.
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We have two forces f1 and f2.
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We know the direction.
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We know the magnitude of each force, and part a of this one wants to find the x and y components of the resultant force.
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We're adding the two together.
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So let's go ahead and find the x and y components of each force.
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So let's bring this 9 -newton force out here for a little bit of clarity, and it's making an angle of 60 degrees with the negative x axis, has a length of 9 newtons.
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So it has an x component that's going in the negative x direction, and it has a y component that's going straight up.
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So this would be f1y, this would be f1x.
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So f1x is the side adjacent to our angle, and we know the hypotenuse, so we're looking at the cosine.
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So the cosine of 60 degrees is equal to the x component divided by the hypotenuse.
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So again, hypotenuse times cosine 60 is going to give us the x component.
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And that's when we plug it into the calculator is going to give us 4 .5 and we do need to be careful because it is pointing in the negative x direction.
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So we're going to slap a negative on there, 4 .5 newtons in the x direction.
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That's our f1x...