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Find ("cos"(2pi+theta)"c o s e c"(2pi+th...

Find `("cos"(2pi+theta)"c o s e c"(2pi+theta)"tan"(pi//2+theta))/("sec"(pi//2+theta)costheta"cot"(pi+theta))`

A

0

B

1

C

-1

D

2

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To solve the expression \[ \frac{\cos(2\pi + \theta) \cdot \csc(2\pi + \theta) \cdot \tan\left(\frac{\pi}{2} + \theta\right)}{\sec\left(\frac{\pi}{2} + \theta\right) \cdot \cos\theta \cdot \cot(\pi + \theta)} \] we will simplify both the numerator and the denominator step by step. ### Step 1: Simplify the numerator 1. **Evaluate \(\cos(2\pi + \theta)\)**: \[ \cos(2\pi + \theta) = \cos(\theta) \quad \text{(since cosine is periodic with period } 2\pi\text{)} \] 2. **Evaluate \(\csc(2\pi + \theta)\)**: \[ \csc(2\pi + \theta) = \csc(\theta) \quad \text{(since cosecant is also periodic with period } 2\pi\text{)} \] 3. **Evaluate \(\tan\left(\frac{\pi}{2} + \theta\right)\)**: \[ \tan\left(\frac{\pi}{2} + \theta\right) = -\cot(\theta) \quad \text{(since tangent shifts by } \frac{\pi}{2}\text{)} \] Putting it all together, the numerator becomes: \[ \cos(2\pi + \theta) \cdot \csc(2\pi + \theta) \cdot \tan\left(\frac{\pi}{2} + \theta\right) = \cos(\theta) \cdot \csc(\theta) \cdot (-\cot(\theta)) \] ### Step 2: Simplify the denominator 1. **Evaluate \(\sec\left(\frac{\pi}{2} + \theta\right)\)**: \[ \sec\left(\frac{\pi}{2} + \theta\right) = -\csc(\theta) \quad \text{(since secant shifts by } \frac{\pi}{2}\text{)} \] 2. **Evaluate \(\cot(\pi + \theta)\)**: \[ \cot(\pi + \theta) = -\cot(\theta) \quad \text{(since cotangent is periodic with period } \pi\text{)} \] Putting it all together, the denominator becomes: \[ \sec\left(\frac{\pi}{2} + \theta\right) \cdot \cos\theta \cdot \cot(\pi + \theta) = (-\csc(\theta)) \cdot \cos\theta \cdot (-\cot(\theta)) \] ### Step 3: Combine the results Now we can substitute the simplified numerator and denominator back into the original expression: \[ \frac{\cos(\theta) \cdot \csc(\theta) \cdot (-\cot(\theta))}{(-\csc(\theta)) \cdot \cos\theta \cdot (-\cot(\theta))} \] ### Step 4: Simplify the fraction The negative signs cancel out, and we have: \[ \frac{\cos(\theta) \cdot \csc(\theta) \cdot \cot(\theta)}{\csc(\theta) \cdot \cos\theta \cdot \cot(\theta)} \] Since the numerator and denominator are identical, we can simplify this to: \[ 1 \] ### Final Result Thus, we have shown that: \[ \frac{\cos(2\pi + \theta) \cdot \csc(2\pi + \theta) \cdot \tan\left(\frac{\pi}{2} + \theta\right)}{\sec\left(\frac{\pi}{2} + \theta\right) \cdot \cos\theta \cdot \cot(\pi + \theta)} = 1 \]

To solve the expression \[ \frac{\cos(2\pi + \theta) \cdot \csc(2\pi + \theta) \cdot \tan\left(\frac{\pi}{2} + \theta\right)}{\sec\left(\frac{\pi}{2} + \theta\right) \cdot \cos\theta \cdot \cot(\pi + \theta)} \] we will simplify both the numerator and the denominator step by step. ...
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