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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

Text Solution

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The correct Answer is:
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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Knowledge Check

  • What is the value of ("cosec "(pi+theta)cot{(9pi//2-theta)}"cosec"^(2)(2pi-theta))/(cot(2pi-theta)sec^(2)(pi-theta)sec{(3pi//2)+theta})

    A
    0
    B
    1
    C
    `-1`
    D
    `oo`
  • The value of (cos (pi+theta)cos(-theta))/(cos(pi-theta)cos((pi)/2+theta)) is

    A
    `tan theta`
    B
    `-tan theta`
    C
    `cot theta`
    D
    `-cot theta`
  • If "sin" (pi "cot" theta) = "cos" (pi "tan" theta), "then cosec" 2 theta is equal to

    A
    `n - (1)/(4)`
    B
    `n + (1)/(4)`
    C
    4n+1
    D
    4n-1
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