If the axes are rotated through an angle 45° in the positive direction without changing the origin,then the co-ordinates of the point (2, 4) in the old system are
1 - 22, 1 + 22
1 + 22, 1 - 22
22, 2
2, 2
A.
If θ he angle of rotation, then the co-ordinates in the new system are x' = xcosθ + ysinθ, y' = ycosθ - xsinθ.
Given that, x' = 2, y' = 4Thus, xcosθ + ysinθ = 2ycosθ - xsinθ = 4Also, θ = π4 ⇒ xcosπ4 + ysinπ4 = 2and cosπ4 - xsinπ4 = 4⇒ x + y = 2 ...iand y - x = 42 ...iiOn adding Eqs. (i) and (ii), we get 2y = 2 + 42⇒ y = 1 + 22On subtracting (i) and (ii), we get 2x = 2 - 42⇒ x = 1 - 22Thus, the co-ordinates of 2, 4 in the old system1 - 22, 1 + 22
x2y2/3 + (xy2)23 = 1
x2 - y2 = 4xy
x2 - y2 = 12xy
x2 - y22 = 16xy
fx = cos2x + sin4xsin2x + cos4x, for x ∈ R, then f(2002) is equal to
1
2
3
4
The function f : R → R is defined by f(x) = cos2x + sin4x for x ∈ R, then f(R) is equal to
(34, 1]
[34, 1)
34, 1
If xn = cosπ4n + isinπ4n, then x1, x2, x3...∞ is equal to
1 + i32
- 1 + i32
1 - i32
- 1 - i32
If z = 3 + 5i, then z3 + z¯ + 198 is equal to
- 3 - 5i
- 3 + 5i
3 - 5i
3 + 5i
If fx = sin2π8 + x2 - sin2π8 - x2, then the period of f is
π3
π2
π
2π
5633
3356
1665
6061
∑k = 13 cos22k - 1π12 is equal to
0
12
- 12
32
If 3 + 2isinθ1 - 2isinθ is a real number and 0 < θ < 2π, then θ is equal to
π6