What will be the final coordinates after rotation of the point P(2, 3, 7) at 90° about X-axis? a) (2, -7, -3) b) (-2, -7, -3) c) (-2, 7, 3) d) (2, -7, 3)
Answer: c Explanation: According to the equations – Xnew = Xold x cosθ – Yold x sinθ = 5 x 0 – 5 x 1 = -5 Ynew = Xold x sinθ + Yold x cosθ = 5 x 1 + 5 x 0 = 5 Znew = Zold = 5
