Rising Nepal Secondary Boarding School

First Terminal Examination 2075

Class: 9 F.M. 50

Time: 1 hr. 30 mins. Subject: Optional Mathematics P.M. 16

Group 'A'

18

  1. Find the co-ordinates of the centroid of a triangle having vertices A(2, 7), B(6, 2) and C(4, 5).
  2. Prove that the triangle is isosceles whose vertices are (1, 1), (4, 1) and (4, -2).
  3. Construct a 2x3 matrix whose elements aij is given by formula aij = i + 2j.
  4. If , find the values of a and b.
  5. If and , find AB and show that AB≠BA.
  6. Find the interior and exterior angles of regular pentagon.
  7. One angle of a triangle is 50g. The remaining angles are in the ratio 2:1. Find the angles of a triangle in degrees.
  8. Simplify:
  9. Express all other trigonometric ratios in terms of sinθ.

Group 'B'

32

  1. A triangle ABC has its vertices at the points A(5, 5), B(-5,1 ) and C(3, -5). Find the length of the median drawn from vertex A.
  2. If and . Find (PQT)T.
  3. If and , find the matrices A and B.
  4. If and then show that A2 – 8B – 17I = O, where I and O are unit and zero matrices of order 2x2.
  5. Find the angle made by minute hand and hour hand at 3:30 o'clock in circular measure.
  6. Prove that: 3(sinθ + cosθ) – (sinθ + cosθ)3 = 2(sin3θ + cos3θ)
  7. Prove that:
  8. Prove that:

-O-