Review on solving inequalities from College Algebra
Type I. Standard Form (coefficients of x are positive and the degree of each factor is 1.)
Example: Solve (x-2)(3x+1)<0. We get two points and 2 on the real line as if we have equality, and we alternate + and - from the right to the left, so our answer to this question is
Type II. Non-Standard Form, but can be made standard by multiplying ''negative(s)''.
Example: Solve (-x-2)(3x+1)<0, this is not in standard form, but we can multiply (-x-2) by -1, which yields, (x+2)(3x+1)>0. So the solution will be
Type III. Can't be made standard, needs to use a table
Example: Solve (3x+1)2(x-2)(x-3)<0. First we get and 3. Next we complete the following table: Therefore the answer is (2,3).
Example: Solve According the table above, the answer will be or
Example: Solve This is equivalent to solve (x-1)(x-3)(x-5)>0. We know that we can apply the ''standard form'' technique to do this one.
Example: Solve This is equivalent to solve (x-1)2(x-3)(x-5)>0 and we can make a table to solve this problem.