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Range Formula Quick Question

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discowisco

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How are the formulas to calculate range in a projectile motion problem different?

As in why is X = Vcos0*t not the same as the R= 2voxvoy/g and R= vo^2sin20/g

Arent all 3 telling me the range? X is the displacement in the horizontal distance thus isnt that the range as well?
 
How are the formulas to calculate range in a projectile motion problem different?

As in why is X = Vcos0*t not the same as the R= 2voxvoy/g and R= vo^2sin20/g

Arent all 3 telling me the range? X is the displacement in the horizontal distance thus isnt that the range as well?

I don't remember ever seeing the second formula (R=2voxvoy/g), maybe I'm forgetting at the moment, but I know the other two.

Both are right. However, for x=vcos0*t, you need to find the time (t) in the y-direction and then plug it into the equation. This is because for projectiles, the time of flight of the object depends on the y-motion only.