What is the value of sin34°cos236° - sin56°sin124°cos28°cos88° + cos178°sin208° = ?
- 2
- 1
2
1
tan54° can be expressed as
sin9° + cos9°sin9° - cos9°
sin9° - cos9°sin9° + cos9°
cos9° + sin9°cos9° - sin9°
sin36°cos36°
If p = Xcosθ - Ysinθ, q = Xsinθ + Ycosθ and p2 + 4pq + q2 = AX2 + BY2, 0 ≤ θ ≤ π2. What is the value of θ ?
π2
π3
π4
π6
If p = Xcosθ - Ysinθ, q = Xsinθ + Ycosθ and p2 + 4pq + q2 = AX2 + BY2, 0 ≤ θ ≤ π2
What is the value of A ?
4
3
-1
0
A.
p = X cosθ- Y sinθ q = X sinθ + Y cosθp2 = X2 cos2θ + Y2 sin2θ - 2XYsinθcosθ q2 = X2 sin2θ + Y2 cos2θ + 2XYsinθcosθ p2 + q2 = X2(sin2θ + cos2θ) + Y2(sin2θ + cos2θ) p2 + q2 = X2 + Y2 pq = (Xcosθ) (Ysinθ) + (Xcosθ) (Ycosθ) - (Ysinθ)(Xsinθ) - (Y sinθ)(Ycosθ) pq = X2sinθcosθ + XYcos2θ - XY sin2θ - Y2sinθcosθ 4pq = 2X2 sin2θ - 2Y2sin2θ + 4XYcos2θ p2 + q2 + 4pq = X2(1 + 2sin2θ) Compare with AX2 + BY2We get, A = 1 + 2sin2θ B = 1 - 2sin2θ4XYcos2θ = 0 ∵ B = 1 - 2sin2θ∵ θ = π4∴ B = 1 - 2sinπ2 = 1 - 2 = - 1
It is given that cosθ - α = a, cosθ - β = bWhat is cosα - β = ?
ab + 1 - a21 - b2
ab - 1 - a21 - b2
a1 - b2 - b1 - a2
a1 - b2 + b1 - a2
It is given that cosθ - α = a, cosθ - β = b. What is sin2α - β + 2abcosα - β = ?
a2 + b2
a2 - b2
b2 - a2
- (a2 + b2)
If sinα + cosα = p, then what is cos22α = ?
p2
p2 - 1
p22 - p2
p2 + 1
If tanθ = 12 and tanφ = 13, then what is the value of θ + ϕ
If cosA = 34, then what is the value of sinA2sin3A2 = ?
58
516
524
732