Thank you guys .. with your help , i reached the answer .
As you said : making the equation in terms of tanθ..
we will get : ( 4.905tan^2(θ) - 30tan(θ) + 7.905 = 0 )
replacing tanθ with x , we get a quadratic equation .. solving it we get 2 answers ..
tan^-1 (x1) = θ1
tan^-1 (x2) = θ2
problem...
I have the same TI-84 plus silver edition as a program on my pc , but I don't know how to use it , can you just tell me how to plot that equation :( , I know I'm asking so much .. but this is the last :)
Oh , sorry the real equation i got was : 30sinθcosθ - 3(cosθ)^2 - 4.905 = 0
not : 30sinθcosθ - (cosθ)^2 - 4.905 = 0
Can you explain how you got the right answer?
Man , I saw a lot of problems on this site similar to mine , and I also saw your reply's :X
and i had no benefits of them , I want some serious hints , i want to go on and solve it :(.
I saw a solution for a very similar question , and they got an equation similar to my equation above , and then they wrote : Using trail and error we get : θ1 and θ2
and now I don't want to waste my whole life putting numbers in the calculator to find the angles , i want the right way to solve...
Homework Statement
A football player attempts a 30m field goal. If he is able to impart a velocity u of 30 m/s to the ball,compute the minimum angle θ for which the ball will clear the crossbar of the goal. (Hint: Let m = tanθ .)
Homework Equations
V0x = V cosθ
V0y = V sinθ
We get t...