multiplying two functions and graphing the result in matlab

To multiply two functions and plot the result in MATLAB, follow these steps:

1. Define the two functions f(x) and g(x).

   main.m
   syms x;
   f(x) = x^2 - 1;
   g(x) = cos(x);
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2. Multiply the functions together to get the resulting function.

   main.m
   h(x) = f(x) * g(x); 
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3. Create a vector of input values for the functions.

   main.m
   x_values = -10:0.1:10;
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4. Evaluate each function at each input value.

   main.m
   f_values = double(subs(f, x, x_values));
   g_values = double(subs(g, x, x_values));
   h_values = double(subs(h, x, x_values));
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5. Plot the original functions and the resulting function on the same graph.

   main.m
   plot(x_values, f_values, 'b', x_values, g_values, 'r', x_values, h_values, 'm');
   legend('f(x)', 'g(x)', 'h(x) = f(x) * g(x)');
   xlabel('x');
   ylabel('f(x), g(x), h(x)');
   title('Plot of f(x), g(x), and h(x)');
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This will create a plot with three curves: one for f(x), one for g(x), and one for h(x) = f(x) * g(x).

Note: The double() function is used to convert the symbolic expression into a numerical array that can be plotted.