I don't know, what I do wrong?:'(

Hello Helpers,

I don't know what to do. Everytime I try to use funktion: slove, this errordialog appeer.

EDU>> clear all

EDU>> slove('x+2=3')

??? Undefined function or method 'slove' for input arguments of type 'char'.

May you can help me find a way... I guessed: I have not the symbolic toolbox, but I found it in C:\Program Files\MATLAB\R2010a Student\toolbox\symbolic

Backgroundinformation: I need to slove equations like this:

v=13,5 m/s (v is the speed of an shooted object)

h=1,70 m (h is the distance to the ground)

g=9,81 m/s^2 (-g is th increas in speed in direction ground)

sy(t) is the actuall distance to the ground

sx(t) is the distance in x direction

I search for sxmax and the best angle of q

sy= v * sin(q) * t + (-g/2)t^2 + h

 0= v * sin(q) * tmax + (-g/2)tmax^2 + h

 0= tmax^2 + (-2*v*sin(q)/g * tmax + (-2*h/g)

tmax= (v*sin(q)/g)+((v*sin(q)/g)^2+(2*h/g))^(1/2)

(p-q-formula taken without - as opinion cause tmax > 0)

sx= v * cos(q) * t

sxmax= v * cos(q) * tmax

sxmax= v * cos(q) * (v*sin(q)/g)+((v*sin(q)/g)^2+(2*h/g))^(1/2)

diff(sxmax)=0

 0=diff( sxmax= v * cos(q) * (v*sin(q)/g)+((v*sin(q)/g)^2+
(2*h/g))^(1/2) )

soo... now I should get q, but I need to get the formula, and not a numeric result.. may you say me a way

sorry for my english, and thanks for reading and may helping

Answer 1

[Honglei Chen]

You typed slove and it should be solve

Answer 2

[Sascha]

-.-

that can't be I wrote it 100 times it can't be 100 the same misstake..., but thanks may it is... I will try it again. If it does not work I will ask again. Now I accept your answer for now