The sixth chapter of MATLAB Learning notes--basic symbolic calculus and differential equations

1.MATLAB you can use the limit command to calculate limits.

>> syms X

>> Limit ((x^3 + 1)/(X^4 + 2))
Ans =
1/2

2. We can call the isequal command in MATLAB to check whether two quantities are equal, and if two are not equal, IsEqual returns 0.

3. We use the following syntax to calculate the limit in Limx→∞f (x) Form: Limit (F,inf).

4. Calculate the left and right limits: we have to pass the function to calculate the limit of the variable and the "Leave", "right" string, separated by commas.

5. By invoking the diff command, we can calculate the symbolic derivative using MATLAB. Simply pass the request-guided function to the diff command. To get the higher order derivative of the function F, we use diff (f,n).

6. You can use the pretty command to make the expression look better.

7. We can use the subs command to substitute a value in the symbolic function, which is fairly straightforward if there is only one variable. If you want to set x=c, then we call Subs (F,c).

8. Use "RO" instead of "O" to tell Matlab to draw a small red circle, using "O" to draw a small black circle. Use the text command to label this minimum point. When you call text, you must tell it which coordinates the text should print in, and pass the text that you want to print.

9. In MATLAB we can use the dsolve command to solve symbolic differential equations. The higher-order derivative is represented by the number of steps in the back of D. So to enter the equation:

　　Y ' + 2y ' = 5sin7x We will write: ' d2y + 2Dy = 5*sin (7*x) '

The sixth chapter of MATLAB Learning notes--basic symbolic calculus and differential equations