Opt practice questions 2.
(a) Name the conic section formed when a plane cuts a right circular cone parallel to its base.

(b)write the equation of line of symmetry of the parabola given by y= ax +bx+c.

3.
(a) Express cos2A in terms of cotA.
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The discrete random variables x and y take integer values with joint probability distribution given by f (x,y) = a(y−x+1) 0 ≤ x ≤ y ≤ 2 or =0 otherwise, where a is a constant. 1 tabulate the distribution and show that a = 0.1.2 find the marginal distributions of x and y. 3 calculate cov(x,y).4 state, giving a reason, whether x and y are independent. 5 calculate e(y|x = 1).