Anyone good at re-arranging equations?

yer_averagejoe · 22 Feb 2013 at 09:24

Hi all, I'm a bit stuck on this one. It's been a while since I've done anything as complex as this.

Basically I'm trying to figure out the angle required for a projectile fired from an elevation to hit a known target.

I've found the equation below:

(from wikipedia)

but this gives the range if you know all other variables. I need to re-arrange this for theta.

If anyone could help me out I would be much obliged!

(and no, this is not homework!)

[FnG]magnolia · 22 Feb 2013 at 09:28

Are you attempting to work out the angles for an assassination?

jsmoke · 22 Feb 2013 at 09:36

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http://en.wikipedia.org/wiki/Trajectory_of_a_projectile

Look at, 'Angle theta required to hit coordinate (x,y)'

yer_averagejoe · 22 Feb 2013 at 09:45

Ha, how didn't I find that! Thanks jsmoke

If anyone still wants a go at re-arranging the origional equation, i'd still be interested in the steps

AndyT · 22 Feb 2013 at 10:19

The result looks like the solution to a quadratic expression. With this in mind I tried to rearrange to get a quadratic for about 5 minutes trying to remember old trig identities but failed miserably. My pure maths days are long behind me. Thank god for MathCAD!

JonJ678 · 22 Feb 2013 at 11:36

Algebra? No thanks, I've got matlab for that.