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sectheta.cottheta=cosectheta, write true...

`sectheta.cottheta=cosectheta`, write true or false.

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To determine whether the statement \( \sec \theta \cdot \cot \theta = \csc \theta \) is true or false, we can follow these steps: ### Step 1: Write down the left-hand side (LHS) The left-hand side of the equation is \( \sec \theta \cdot \cot \theta \). ### Step 2: Substitute the definitions of secant and cotangent We know that: - \( \sec \theta = \frac{1}{\cos \theta} \) - \( \cot \theta = \frac{\cos \theta}{\sin \theta} \) Substituting these definitions into the LHS gives us: \[ \sec \theta \cdot \cot \theta = \left(\frac{1}{\cos \theta}\right) \cdot \left(\frac{\cos \theta}{\sin \theta}\right) \] ### Step 3: Simplify the expression Now, we can simplify the expression: \[ \sec \theta \cdot \cot \theta = \frac{1 \cdot \cos \theta}{\cos \theta \cdot \sin \theta} = \frac{1}{\sin \theta} \] ### Step 4: Recognize the definition of cosecant We know that: \[ \csc \theta = \frac{1}{\sin \theta} \] ### Step 5: Compare LHS and RHS Now we can compare the simplified LHS with the right-hand side (RHS): \[ \frac{1}{\sin \theta} = \csc \theta \] ### Conclusion Since both sides are equal, we conclude that: \[ \sec \theta \cdot \cot \theta = \csc \theta \] Thus, the statement is **true**.
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ICSE-TRIGONOMETRICAL RATIOS OF STANDARD ANGLES-EXERCISE 23(A)
  1. If sinx=cosy, write the relation between x and y, if both the angles x...

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  2. If sinx=cosy, then x+y=45^(@), write true or false.

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  3. sectheta.cottheta=cosectheta, write true or false.

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  4. For any angle theta, state the value of : " "sin^(2)theta+cos...

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  5. State for any acute angle theta whether : sintheta increases or decr...

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  6. State for any acute angle theta whether : costheta increases or decr...

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  7. State for any acute angle theta whether : tantheta increases or decr...

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  8. If sqrt(3)=1*732, find (correct to two decimal places) the value of th...

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  9. Evaluate : (cos3A-3cos4A)/(sin3A+2sin4A)," when "A=15^(@).

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  10. Evaluate : (3sin3B+2cos(2B+5^(@)))/(2cos3B-sin(2B-10^(@))), when B...

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  11. Find the value of : sin30^(@)cos30^(@)

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  12. Find the value of : tan30^(@)tan60^(@)

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  13. Find the value of : cos^(2)60^(@)+sin^(2)30^(@)

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  14. Find the value of : cosec^(2)60^(@)-tan^(2)30^(@)

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  15. Find the value of : sin^(2)30^(@)+cos^(2)30^(@)+cot^(2)45^(@)

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  16. Find the value of : cos^(2)60^(@)+sec^(2)30^(@)+tan^(2)45^(@)

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  17. Find the value of : tan^(2)30^(@)+tan^(2)45^(@)+tan^(2)60^(@)

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  18. Find the value of : (tan45^(@))/(cosec30^(@))+(sec60^(@))/(cot45^(@)...

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  19. Find the value of : 3sin^(2)30^(@)+2tan^(2)60^(@)-5cos^(2)45^(@)

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  20. Prove that : sin60^(@)cos30^(@)+cos60^(@).sin30^(@)=1

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