49T+245e^(-T/5)-545 = 0

i am totally new to matlab. with which func and command could I get the value of T?

sorry for the too much elementary question. Just started to learn D.E.s..

[androidguy]

you can look here for solving your question

http://www.mathworks.com/help/symbolic/solve-a-single-differential-equation.html

[José-Luis]

That's not a differential equation though.

Answer 1

[José-Luis]

fzero()

 fun = @(x) 49*x + 245*exp(-x/5) - 545;
 result = fzero(fun,0)

Answer 2

[Walter Roberson]

syms T
solution = solve(49*T+245*exp(-T/5)-545 == 0)

The answer will be in terms of the Lambert W function. If you want to see the decimal equivalent,

double(solution)

Answer 3

[yubo liu]

I try the above methods,but why do i get different results,fun = @(x) 49*x + 245*exp(-x/5) - 545; result = fzero(fun,0) the first resule is -6.2180,and the second method syms T solution = solve(49*T+245*exp(-T/5)-545 == 0),the second result is 10.5116 why? hope your answers

[Walter Roberson]

Both might be right. fzero never tries to find all solutions for a function. solve only tries to find multiple solutions for polynomials

[Star Strider]

When in doubt, plot it:

fun = @(x) 49*x + 245*exp(-x/5) - 545;
t = linspace(-15, 25, 500);

figure(1)
plot(t, fun(t))
grid

[Walter Roberson]

There are, by the way, an infinite number of solutions; two of the solutions are real.