If S1, S2 and S3 are the sums of n, 2n and 3n terms of an arithmetic progression respectively, then
S2 = 3S3 - 2S1
S3 = 4(S1 + S2)
S3 = 3(S2 - S1)
S3 = 2(S2 + S1)
C.
S3 = 3(S2 - S1)
Let the first term and common difference of an AP be a and d respectively
The sides AB, BC, CA of triangle ABC have 3, 4 and 5 interior points respectively on them. Find the number of triangles that can be constructed using these points as vertices
201
120
205
435
The equation of the parabola having the focus at the point (3, - 1) and the vertex at (2, - 1)is
y2 - 4x - 2y + 9 = 0
y2 + 4x + 2y - 9 = 0
y2 - 4x + 2y + 9 = 0
y2 + 4x - 2y + 9 = 0
The equation of lines joining the origin to the points of intersection of y = x + 3 and 4x2 + 4y2 = 1 is
36(x2 + y2) = (x - y)2
12(x2 + y2) = (x + y)2
9(x2 + y2) = 4(x - y)2
None of the above
The angle of elevation of a jet fighter from a point A on the ground is 60°. After a flight of 10s, the angle of elevation changes to 30°. If thejet is flying at a speed of 432 km/h. Find the constant height at which thejet is flying.
Find the equation of tangents to the ellipse which cut off equal intercepts on the axes.
None of the above