Explanation

135° is in the second quadrant, where cosine is negative.

Therefore, Cos 135° = -√2/2.

Last verified on 18-07-2026

Explanation

Co-prime numbers have no common factor except 1.

Their HCF (Highest Common Factor) is 1.

2, 4

• Factors of 2 = 1, 2
• Factors of 4 = 1, 2, 4
• Common factors = 1, 2
• HCF = 2  Not co-prime

3, 6

• Factors of 3 = 1, 3
• Factors of 6 = 1, 2, 3, 6
• Common factors = 1, 3
• HCF = 3  Not co-prime

4, 10

• Factors of 4 = 1, 2, 4
• Factors of 10 = 1, 2, 5, 10
• Common factors = 1, 2
• HCF = 2  Not co-prime

2, 9

• Factors of 2 = 1, 2
• Factors of 9 = 1, 3, 9
• Common factor = 1
• HCF = 1 Co-prime

Last updated 17 july 2026 by NA

Explanation

• The sum of the three interior angles of a triangle is 180°.
• This rule applies to all types of triangles.
• If two angles are known, the third angle = 180° − (sum of the other two angles).
• It is a basic rule of geometry.
• This property is known as the Angle Sum Property.

Last updated 17 july 2026 by NA

Explanation

Formula: nCr = n! / r!(n-r)!

Here n = 6 girls, r = 3 girls to select

6C3 = 6! / 3!(6-3)!  

= 6! / 3!3!  

= (6 x 5 x 4) / (3 x 2 x 1)  

= 120 / 6  

= 20

Last verified on 11-07-2026

Explanation

Any non-zero number raised to the power 0 is always 1.

So, (1/2)° = 1

Last verified on 10-07-2026