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Good people please help me!!!! ​

Good people please help me!!!! ​-example-1

1 Answer

8 votes

Answer:

a) |sec(θ)|

b) 2cot(2x)

Explanation:

Trig identities are used to simplify these expressions. Several are used:

  • tan(180°-x) = -tan(x)
  • cot(90°-x) = tan(x)
  • 1 +tan(x)² = sec(x)²
  • tan(x) = sin(x)/cos(x)
  • sin(2x) = 2sin(x)cos(x)
  • cot(x) = cos(x)/sin(x)

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a.


√(1-\tan(180^\circ-\theta)\cot(90^\circ-\theta))=√(1-(-\tan(\theta))\tan(\theta))\\\\=√(1+\tan^2(\theta))=√(\sec^2(\theta))=\boxed

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b.


(\cos(2x)\tan(x))/(\sin^2(x))=(\cos(2x))/(\sin^2(x))\cdot(\sin(x))/(\cos(x))=(\cos(2x))/(\sin(x)\cos(x))\\\\=(\cos(2x))/(\left((\sin(2x))/(2)\right))=2(\cos(2x))/(\sin(2x))=\boxed{2\cot(2x)}

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