6. If sin 0 + 2 cos 0 = 1 prove that 2 sin 0 - cos 0 = 2.
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Answered by
1
Answer:
sin o=2
cos o=0
tan o=2/0
now,tan=p/b=2/0
p=2 and b=0
please mark as brainlist
Answered by
2
Given, sin θ + 2cos θ = 1
Squaring on both sides, we get
Now, (sin θ + 2cos θ)2 = 12
=> sin2 θ + 4cos2 θ + 4*sin θ * cos θ = 1
=> 1 - cos2 θ + 4(1 - sin2 θ) + 4 * sin θ * cos θ = 1 [Since sin2 θ + cos2 θ = 1]
=> 1 - cos2 θ + 4 - 4 * sin2 θ + 4 * sin θ * cos θ = 1
=> 5 - cos2 θ - 4 * sin2 θ + 4 * sin θ * cos θ = 1
=> 5 - 1 = cos2 θ + 4 * sin2 θ - 4 * sin θ * cos θ
=> cos2 θ + 4 * sin2 θ - 4 * sin θ * cos θ = 4
=> 4 * sin2 θ + cos2 θ - 4 * sin θ * cos θ = 22
=> (2sin θ - cos θ)2 = 22
=> 2sin θ - cos θ = ±2
Hence proved.
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