Govt. Exams
Entrance Exams
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The HCF of 36 and 48 is:
Correct Answer:
C. 12
EXPLANATION
36 = 2²×3², 48 = 2⁴×3. HCF = 2²×3 = 12
If log₂ x = 5, then x = ?
Correct Answer:
C. 32
EXPLANATION
log₂ x = 5 means 2⁵ = x, therefore x = 32
What is the sum of angles in a polygon with 8 sides?
Correct Answer:
A. 1080°
EXPLANATION
The sum of interior angles in any polygon depends only on the number of sides, following a fixed mathematical relationship.
Step 1: Identify the Formula for Sum of Interior Angles
For any polygon with n sides, the sum of all interior angles is given by the formula:
\[\text{Sum of interior angles} = (n - 2) \times 180°\]
Step 2: Substitute the Number of Sides
Since the polygon has 8 sides, substitute n = 8 into the formula:
\[\text{Sum} = (8 - 2) \times 180°\]
\[\text{Sum} = 6 \times 180°\]
\[\text{Sum} = 1080°\]
The sum of angles in a polygon with 8 sides is 1080°.
Answer: (A) 1080°
If sin θ = 3/5 and θ is in the second quadrant, find cos θ.
Correct Answer:
A. -4/5
EXPLANATION
In second quadrant, cos is negative. Using sin²θ + cos²θ = 1: cos²θ = 1 - 9/25 = 16/25, so cos θ = -4/5
