Logical operators (-and, -or, -not) in PowerShell - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if both conditions are true using the correct logical operator.

PowerShell

if ($a -gt 5 [1] $b -lt 10) { Write-Output "Both true" }

Drag options to blanks, or click blank then click option'

A-and

B-or

C-not

D-xor

Attempts:

3 left

💡 Hint

Common Mistakes

Using -or instead of -and causes the condition to be true if either is true.

Using -not negates a single condition, not both.

The -and operator checks if both conditions are true.

2fill in blank

medium

Complete the code to check if either condition is true using the correct logical operator.

PowerShell

if ($x -eq 0 [1] $y -eq 1) { Write-Output "At least one is true" }

Drag options to blanks, or click blank then click option'

A-and

B-xor

C-not

D-or

Attempts:

3 left

💡 Hint

Common Mistakes

Using -and requires both conditions to be true, which is not what we want here.

Using -not negates a condition, not combines two.

The -or operator returns true if at least one condition is true.

3fill in blank

hard

Fix the error in the code by choosing the correct logical operator to negate the condition.

PowerShell

if ([1] ($status -eq 'Success')) { Write-Output "Not successful" }

Drag options to blanks, or click blank then click option'

A-or

B-not

C-and

D-xor

Attempts:

3 left

💡 Hint

Common Mistakes

Using -and or -or here causes syntax errors or wrong logic.

For negation, only -not works correctly.

The -not operator negates the condition, so it is true when the status is not 'Success'.

4fill in blank

hard

Fill both blanks to create a condition that is true when $a is greater than 10 and $b is not equal to 5.

PowerShell

if ($a [1] 10 [2] $b -ne 5) { Write-Output "Condition met" }

Drag options to blanks, or click blank then click option'

A-gt

B-lt

C-and

D-or

Attempts:

3 left

💡 Hint

Common Mistakes

Using -lt instead of -gt reverses the comparison.

Using -or allows the condition to be true if only one side is true.

-gt means greater than, and -and combines both conditions to be true.

5fill in blank

hard

Fill all three blanks to create a condition that is true when $x is less than 5 or $y is not equal to 10, but not when $z is true.

PowerShell

if (($x [1] 5 [2] $y -ne 10) -and [3] $z) { Write-Output "Complex condition met" }

Drag options to blanks, or click blank then click option'

A-lt

B-or

C-and

D-not

Attempts:

3 left

💡 Hint

Common Mistakes

Using -and instead of -or changes the logic.

Not negating $z causes the condition to behave incorrectly.

-lt means less than, -or combines the first two conditions, and -not negates the last condition.

Practice

1. Which logical operator in PowerShell means both conditions must be true for the whole expression to be true?

easy

A. -xor

B. -or

C. -and

D. -not

Solution

1. Step 1: Understand the meaning of -and

   The -and operator requires both conditions to be true for the entire expression to be true.

2. Step 2: Compare with other operators

   -or means one or both conditions true; -not reverses a condition; -xor means exactly one true.

3. Final Answer:

   -and -> Option C

4. Quick Check:

   -and = both true [OK]

Hint: Remember: -and means both must be true [OK]

Common Mistakes:

• Confusing -and with -or
• Thinking -not means both true
• Mixing -and with -xor

2. Which of the following is the correct syntax to check if variable $a is greater than 5 AND $b is less than 10 in PowerShell?

easy

A. if ($a -gt 5 && $b -lt 10) { Write-Output 'true' }

B. if ($a -gt 5 -and $b -lt 10) { Write-Output 'true' }

C. if ($a > 5 && $b < 10) { Write-Output 'true' }

D. if ($a > 5 -and $b < 10) { Write-Output 'true' }

Solution

1. Step 1: Identify PowerShell logical operator syntax

   PowerShell uses -and, -or, -not for logical operations, not && or > for comparisons.

2. Step 2: Check comparison operators and logical operator

   -gt and -lt are correct for greater than and less than; -and is correct for AND.

3. Final Answer:

   if ($a -gt 5 -and $b -lt 10) { Write-Output 'true' } -> Option B

4. Quick Check:

   PowerShell uses -and, -gt, -lt [OK]

Hint: Use -and, -gt, -lt for PowerShell conditions [OK]

Common Mistakes:

• Using && instead of -and
• Using > or < instead of -gt or -lt
• Mixing syntax from other languages

3. What is the output of this PowerShell code?

$a = $true
$b = $false
if ($a -or $b) { 'Yes' } else { 'No' }

medium

A. Yes

B. No

C. false

D. true

Solution

1. Step 1: Evaluate $a -or $b

   $a is true, $b is false; -or means if either is true, result is true.

2. Step 2: Determine if block output

   Since $a -or $b is true, the if block runs and outputs 'Yes'.

3. Final Answer:

   Yes -> Option A

4. Quick Check:

   -or with true and false = true [OK]

Hint: -or is true if any condition is true [OK]

Common Mistakes:

• Thinking both must be true for -or
• Confusing output with boolean true/false
• Ignoring the if-else structure

4. Identify the error in this PowerShell statement:

if (-not $a -and $b) { Write-Output 'Valid' }

medium

A. No error, statement is correct

B. Incorrect use of -and operator

C. Variables $a and $b are undefined

D. Missing parentheses around -not condition

Solution

1. Step 1: Understand operator precedence

   -not has higher precedence; without parentheses, it applies only to $a, but combined with -and can cause confusion.

2. Step 2: Fix with parentheses

   Use parentheses: if ((-not $a) -and $b) { ... } to clarify logic and avoid errors.

3. Final Answer:

   Missing parentheses around -not condition -> Option D

4. Quick Check:

   Use parentheses with -not in complex expressions [OK]

Hint: Use parentheses to group -not conditions [OK]

Common Mistakes:

• Ignoring operator precedence
• Assuming -not applies to whole expression
• Not using parentheses for clarity

5. You want to write a PowerShell condition that is true only when $x is NOT equal to 10 AND $y is either 5 or 7. Which is the correct expression?

hard

A. if (($x -ne 10) -and ($y -eq 5 -or $y -eq 7)) { 'Match' }

B. if (-not ($x -eq 10 -and $y -eq 5 -or $y -eq 7)) { 'Match' }

C. if (-not $x -eq 10 -and $y -eq 5 -or $y -eq 7) { 'Match' }

D. if ($x -ne 10 -or $y -eq 5 -and $y -eq 7) { 'Match' }

Solution

1. Step 1: Break down the condition

   $x must NOT be 10, so $x -ne 10; $y must be 5 OR 7, so ($y -eq 5 -or $y -eq 7).

2. Step 2: Combine with -and and parentheses

   Use parentheses to group $y conditions and combine with $x condition using -and.

3. Final Answer:

   if (($x -ne 10) -and ($y -eq 5 -or $y -eq 7)) { 'Match' } -> Option A

4. Quick Check:

   Use parentheses to group OR inside AND [OK]

Hint: Group OR conditions inside parentheses when combined with AND [OK]

Common Mistakes:

• Missing parentheses causing wrong logic
• Using -or instead of -and between main conditions
• Incorrect placement of -not operator