Review and summary of the homework

1. The solve command:

Without evaluating the following code, try to predict exactly what the output will be:

> solve( x^2 - x - 2 = 0, x );
solve( {a+b = 3, a-b = 1}, {a,b} );

Now evaluate the expressions the check your predictions.

Exercise : Use the solve command to find a pair of numbers whose sum is 10 and whose product is 21. Try it now.

> solve( {c+d=10, c*d=21});

2. The plot command:
Plot the polynomial for = to 4.
Does this range show all the roots to this polynomial?
Title your plot "Cubic Polynomial."

> plot(x^3-16*x^2+7, x=-4..4,title="Cubic Polynomial");

Polynomial with a power of three should have three roots shown.