tanA = 2sinA
2007-04-25 17:43:41 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
sin A / cos A = 2 sin A
<=> sin A = 2 sin A cos A (cos A not 0)
<=> sin A (1 - 2 cos A) = 0
<=> sin A = 0 or cos A = 1/2.
So A = kπ or (2k + 1/3)π, for k ∈ Z.
2007-04-25 17:46:36 · answer #1 · answered by Scarlet Manuka 7 · 1⤊ 0⤋
tanA = 2sinA
tanA - 2sinA = 0
sinA/cosA - 2sinA = 0
(sinA - 2sinAcosA)/ cosA = 0
[sinA(1 - 2cosA)] / cosA = 0
=> [sinA(1 - 2cosA)] = 0
sinA = 0
A(in degrees) = 0, 180
A(in radians) = 0, pi
or
1-2cosA = 0
cosA = 1/2
A(in degrees) = 60, 360-60=300
A(in radians) = pi/3, 2pi - pi/3 = 5pi/3
Conclusion,
A(in degrees) = 0, 60, 180, 300
A(in radians) = 0, pi/3, pi, 5pi/3
2007-04-26 00:53:13 · answer #2 · answered by QiQi 3 · 0⤊ 0⤋
tana=2sina
sina/cosa=2sina
cosa=1/2
a=60 degree
2007-04-26 00:54:04 · answer #3 · answered by Moaz A 1 · 0⤊ 0⤋
sinA/cosA = 2sinA
cosA = 1/2
A = 60 degrees or pi/3 radians.
In radians A = 2n.pi ± pi/3
2007-04-26 00:49:37 · answer #4 · answered by gudspeling 7 · 0⤊ 0⤋
y/x = A = 2y/h cancel out the y's
2x = h
so A = 60 degrees
2007-04-26 00:49:41 · answer #5 · answered by Wocka wocka 6 · 0⤊ 0⤋