Maple Tutor

Part 2: Variables

1. Enter
   x:=3; y:=2
   Note that Maple uses a semicolon to separate two statements which are on the same line.  Both statements are executed and the results displayed.
2. Enter
   2*x + y
3. The result of the preceding step follows from the fact that the variable x has been assigned the value 3 and the variable y has been assigned the value 2. Check this by entering
   x; y
4. Enter the following line. Note that it ends with a colon.
   z:=5:
   Now, enter
   z
   Entering a command with a colon has the same long-term effect as entering it without, but nothing is displayed afterwards.
5. Use pencil and paper to decide what number xy² + 3z represents, and then check your answer by entering
   x*y^2+3*z
   Use your mouse to return to the expression just entered, replace the 3 by 4, and press RETURN.
6. Suppose we want to remove the identification of x with 3. Enter
   x:='x'
   Check this by entering
   x
   
   
   
   Now remove the identifications of y with 2 and z with 5. Check by entering
   x*y*z
   You should see
   xyz
   as the output.
7. Maple distinguishes between := and =. The first is used for definitions. The equals sign alone is used to enter equations. Check this by entering
   s^2 - s - 1 = 0
   Use your mouse to highlight this expression, click the right mouse button, and select "Solve"  > "Solve for Variable" > "s" from the popup menus.  Maple should make an arrow pointing to the desired output. (In Maple versions 11 and higher the arrow is labeled "solve for s".)

8. Enter
   2 + 3
   and then
   % + 5
   The percent sign has the value of the last quantity calculated. Check this by entering
   x*y
   and then
   % + z