If a, b, c are in GP (a> 1, b > 1, c > 1), then for any real number x (with x > 0, x 1), are in
GP
AP
HP
GP but not in HP
A line through the point A(2, 0) which makes an angle of 30° with the positive direction of x-axis is rotated about A in clockwise direction through an angle 15°. Then, the equation of the straight line in the new position is
The equation of the tangent to the conic x2 - y2 - 8x + 2y + 11 = 0 at (2, 1) is
x + 2 = 0
2x + 1 = 0
x + y + 1 = 0
x - 2 = 0
The total number of tangents through the point ( 3, 5) that can be drawn to the ellipses 3x2 + 5y2 = 32 and 25x + 9y2 = 450 is
0
2
3
4
C.
3
Let S1 = 3x2 + 5y2 - 32
and S2 = 25x2 + 9y2 - 450
At point (3, 5)
S1 = 3(3)2 + 5(5)2 - 32 = 120 > 0
and S2 = 25(3)2 + 9(5)2 - 450
= 225 + 225 - 450 = 0
Thus, Point (3, 5) lies outside the first ellipse and for second ellipse lies on the ellipse.
Hence, two tangents for first ellipse and one tangent for second ellipse can be drawn.
A particle is moving in a straight line. At time t, the distance between the particle from its starting point is given by x = t - 6t2 + t3. Its acceleration will be zero at
t = 1 unit time
t = 2 unit time
t = 3 unit time
t = 4 unit time