Tidbits about Inequality
Graphing
Can I shade just the answer without
the overlaps? 
You can shade the area between two graphs. The Shade command shades the area that
is specifically above the lower function and below the upper
function.
Only the areas where lowerfunc < upperfuncare shaded.
Shade (lowerfunc, upperfunc) 
Demo: Solve

(shading only the answer) 

 Enter Y_{1 } = x + 1 and Y_{2} = x + 1
 Graph
to determine which graph is the "upperfunc". In this problem it
is Y_{1}. Think of the "upperfunc"
as "function
to shade below". (Be careful not to confuse the "upper"
function with the "greater than" symbol.)
 Press DRAW (2nd
PRGM) and choose option #7
Shade(
 Type Shade(Y_{2},
Y_{1})



The Shade parameters are:
Shade(function to shade above, function to
shade below)
Additional
parameters allow:
Shade(function to
shade above, function to shade below, left bound, right bound,
the pattern (a number from 1 to 4), pattern resolution (a number
from 1 to 8))


Can I make
it shade ONLY between three lines? 

You have to be rather creative
to get the calculator to shade only between three lines.
In most cases, it will be more work than worth.
Demo:
Solve

Method 1: (All
shaded) Enter the
inequalities into Y_{1},
Y_{2} and Y_{3} and choose the proper "shade
above" or "shade below"
builtin icons in front of the Y=. As you can see at the right, all
areas are shaded and the answer is the darkest
shading. 

Method 2:
(Answer only, shaded)
Enter
the inequalities without the builtin "shade
above/below" icons. This method will use the
Boolean operators.
Look carefully at the Y_{3} entry.
If the statement is true, a value of 1 is being
multiplied times the function, and if false a value
of 0. The * is
needed so that the function is not calculated as a
composition of functions.
Then Shade
(Y_{3}, Y_{4}) to get the
solid figure. Whew! 
Shade
(Y_{3}, Y_{4}) to see graph. 

What about shading left or
right of a vertical line? 
You will need to engage the DRAW
commands to create vertical lines for shading.
Finding
Your Way Around TABLE of CONTENTS
