Help in Entering Inequalities

To enter an inequality, you can use your computer keyboard interchangably with a calculator keypad.

Key Equivalents
Entering Inequalities in x (or X)
Key
Input (Keyboard) Form
>=
<=
And
&&
|x|
abs(x)
sqrt(x)
π
pi
Mathematical Form
Input (Keyboard) Form
2(7x-3)<=12x+16
x^2>=x+1
(2x+1)/(x-5)<=3
x/(x+2)<1/x
1<=3x+4<16
1<abs(x-1)<=3

Entering Inequalites in x and y (or X and Y)

Mathematical Form
Input (Keyboard) Form (And=&&)
2x+y>=6
x^2+y^2>1
4x-5y<=0&&2x-y>=2
x>=0&&y>=0&&x+y>=2&&2x+y>=4
y>=x+2&&y<=5-x^2
y>=(x-2)^2&&y<=4-x^2

You can use parentheses, ( ), square brackets, [ ], or curly braces, { }, to group terms.

Terms in x may be entered as numbers (coefficients) times powers in x. You can use "*" for multiplication, or in the case of a number times x, you can abbreviate, say,"3*x" by "3x" but not "x3"; also, "x*x" cannot be abbreviated to "xx".

Coefficients may be entered as integers (like 2 or –3), rational numbers (ratios of integers, like (1/2) or (–5/4)), or decimals (like 1.52 or –7.6). We automatically convert all decimals to their rational number equivalents (for example, 1.52 = 38/25). Fractional powers can be entered using parentheses, as in 3^(1/2) or x^(-1/3).

Use pi for π (approximately 3.14) and e for the base e (approximately 2.72) of natural logarithms.

When entering any function, like sqrt for the square root, the argument (term in x) following the name needs to be enclosed in paired parentheses. So, "sqrtx" is incorrect, as is "sqrt(x", but "sqrt(x)" is correct.

More Information

For further illustrations of valid input, see how inequalities are entered in Examples of Inequalites in One Variable and Examples of Inequalites in Two Variables.

 

 

       

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