Plotting symbolic equation in matlab

whats wrong with this?

Here i tried to plot a sybolic equation for range x=[1,20] but it shows

How to fix it .and plotting the curve

Answer 1

[Cris LaPierre]

Try creating your symbolic equation using the approach shown in the examples here.

syms eq(x)
eq(x) = (sin(sqrt(x)+5)*exp(sqrt(x)))/sqrt(x)

eq(x) = 

fplot(eq,[0 20])

[Md. Ashikur Rahman Any]

If i want to get all the intersecting point of x axis for a particular range like the graph below.For instance here the intersecting ponit is in range of 1 to 400.

how to get that ?

Thanks in Advance

[Cris LaPierre]

I think you want to use vpasolve. It does not appear to be able to return all solutions at once, so you'll have to define intervals to search in. See this example.

syms x
eq = (sin(sqrt(x)+1)*exp(sqrt(x)))/sqrt(x)==0

eq = 

vpasolve(eq,x)

ans = 

70.976883688265468138734558699208

% restricting range
vpasolve(eq,x,[0 10])

ans = 

4.5864190939097721419092042333171

vpasolve(eq,x,[10 30])

ans = 

27.912046989998261521487390466387