Work Done by F from Po to P1 -90Nm

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A constant force F = -7i - 6j - 9k moves an object along a straight line from point (-3, 3, -3) to point (-3, 0, 5).

Find the work done if the distance is measured in meters and the magnitude of the force is measured in Newtons.

So basically I know I need to do a dot product of F with the vector between the two points, but I keep doing my math wrong.

Vector between points let's call them Po (-3,3,-3) and P1 (-3,0,5)
I found to be (0,-3,8)

So I then did the dot product between F and the Vector between Po and P1
I got -90, but my answer is wrong?
 
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Ahah a foolish negative mistake thanks for looking guys, but I found the answer
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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