All SAT II Math I Resources
Example Questions
Example Question #11 : Real And Complex Numbers
Which of the following choices gives a sixth root of sixty-four?
All of these
All of these
Let be a sixth root of 64. The question is to find a solution of the equation
.
Subtracting 64 from both sides, this equation becomes
64 is a perfect square (of 8) The binomial at left can be factored first as the difference of two squares:
8 is a perfect cube (of 2), so the two binomials can be factored as the sum and difference, respectively, of two cubes:
The equation therefore becomes
.
By the Zero Product Principle, one of these factors must be equal to 0.
If , then ; if , then . Therefore, and 2 are sixth roots of 64. However, these are not choices, so we examine the other polynomials for their zeroes.
If , then, setting in the following quadratic formula:
If , then, setting in the quadratic formula:
Therefore, the set of sixth roots of 64 is
.
All four choices appear in this set.
Example Question #41 : Number Theory
Let and be complex numbers. and denote their complex conjugates.
Evaluate .
None of these
None of these
Knowing the actual values of and is not necessary to solve this problem. The product of the complex conjugates of two numbers is equal to the complex conjugate of the product of the numbers; that is,
, so , and
,
which is not among the choices.
Example Question #41 : Number Theory
denotes the complex conjugate of .
If , then evaluate .
None of these
Applying the Power of a Product Rule:
The complex conjugate of an imaginary number is ; the product of the two is
, so, setting in the above pattern:
Consequently,
Example Question #1 : Mathematical Relationships
Evaluate the expression.
Follow the correct order of operations: parenthenses, exponents, multiplication, division, addition, subtraction.
First, evaluate any terms in parenthesis.
Next, evaluate the exponent.
Divide.
Finally, add.
Example Question #1 : Elementary Operations
Evalute the expression:
Follow the correct order of operations: parentheses, exponents, multiplication, division, addition, subtraction. (This is typically abbreviated as PEMDAS. Note that both multiplication and division, and addition and subtraction, are equal to each other in terms of rank, so when both are present, solving the equation proceeds from left to right).
First, simplify anything in parentheses.
Next, simplify any terms with exponents.
Now, perform multiplication.
Since all we are left with is addition and subtraction, we perform simplification from left to right.
Thus, our answer is:
Example Question #1 : Elementary Operations
Add in modulo 7:
In modulo 7 arithmetic, a number is congruent to the remainder of its division by 7.
Therefore, since and ,
,
and the correct response is 3.
Example Question #1 : Mathematical Relationships
Add:
To solve , make sure the digits are aligned with the correct placeholder. It is also possible to add term by term.
The correct answer is:
Example Question #5 : Mathematical Relationships
Evaluate: .
Step 1: Recall PEMDAS...
Parentheses, Exponents, Multiplication, Division, Addition, Subtraction.
Step 2: Perform the evaluation in separate pieces...
Step 3: Replace the values and keep the signs..
Step 4: Evaluate:
Example Question #6 : Mathematical Relationships
Find the sum of the numbers:
Add all the ones digits.
Add the tens digits with the two as the carryover.
Combine this value with the ones digit of the first number.
The answer is:
Example Question #7 : Mathematical Relationships
Evaluate:
Add the ones digits.
Add the tens digits with the tens digit of the previous number as carryover.
Repeat the process with the hundreds digits.
Combine this number with the ones digits of the previous calculations.
The answer is:
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