All ISEE Upper Level Quantitative Resources
Example Questions
Example Question #121 : How To Find The Solution To An Equation
If is negative and , then what is ?
The equation has no negative solution.
, so either
or
We solve both equations separately:
Since the negative solution is being requested, we choose .
Example Question #122 : How To Find The Solution To An Equation
Give the solution set of the equation:
Either
or ,
so we solve the equations separately:
or
The solution set is
Example Question #121 : How To Find The Solution To An Equation
Which of the folllowing is a true statement?
The equation has three solutions.
The equation has no solution.
The equation has infinitely many solutions.
The equation has one solution.
The equation has two solutions.
The equation has infinitely many solutions.
Since the absolute value of a nonnegative number is the number itself, and the absolute value of a negative number is its (positive) opposite, we have to examine up to three cases: , , and .
However, let us examine that third case.
This makes and negative, so the equation can be rewritten:
This statement is identically true. Therefore, all values of less than work, and we have already proved that there are infinitely many solutions. We do not need to go further.
Example Question #124 : How To Find The Solution To An Equation
Which of the following is a true statement?
,
so
Using two substitutions:
The correct choice is .
Example Question #125 : How To Find The Solution To An Equation
Which of the following is a true statement?
Similarly,
By substitution:
Example Question #126 : How To Find The Solution To An Equation
Express in terms of .
Example Question #122 : How To Find The Solution To An Equation
Which of the following is true of ?
Example Question #123 : How To Find The Solution To An Equation
Which of the following is true of ?
None of the other responses gives a correct answer.
Example Question #124 : How To Find The Solution To An Equation
Define to be the function graphed in the figure above, and .
Evaluate
is outside the domain of
From the diagram below, it can be seen that .
, so
Therefore,
.
Example Question #125 : How To Find The Solution To An Equation
Define to be the function graphed in the figure above, and .
Evaluate
is outside the domain of
.
Examine the diagram below.
As can be seen, . Therefore, .