If the value of sin A + cosec A = 2, then what is the value of sin7 A ...
It is given that sin A + cosec A = 2 ……(i)
On putting A = 900, then above condition will satisfy
sin 900 + cosec 900 = 2
or, 1 + 1 = 2 (as the equation satisfies, so, A = 900)
Now, sin7 A + cosec7 A = ?
⇒ sin7 900 + cosec7 900
⇒ 17 + 17
= 2
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If the value of sin A + cosec A = 2, then what is the value of sin7 A ...
To find the value of sin7A cosec7A, we need to use the given information that sinA cosecA = 2.
1. Understanding the given information:
- We know that sinA cosecA = 2.
- CosecA is the reciprocal of sinA. Therefore, cosecA = 1/sinA.
2. Finding the value of sinA:
- Since sinA cosecA = 2, we can rewrite it as sinA * (1/sinA) = 2.
- Simplifying the equation, we get sinA = 2.
- Thus, sinA = 2.
3. Using the value of sinA to find sin7A:
- To find sin7A, we can use the property of periodicity of the sine function.
- The sine function has a period of 2π, which means that sin(x + 2π) = sin(x).
- Therefore, sin(7A) = sin(2π + 7A).
- We can further simplify this by noticing that sin(2π + 7A) = sin(2π)cos(7A) + cos(2π)sin(7A).
- Since sin(2π) = 0 and cos(2π) = 1, the equation becomes sin(7A) = 0*cos(7A) + 1*sin(7A).
- Simplifying, we find sin(7A) = sin(7A).
- Thus, sin(7A) = sin(7A).
4. Using the value of sinA to find cosec7A:
- To find cosec7A, we can use the property of the cosecant function, which is the reciprocal of the sine function.
- Therefore, cosec7A = 1/sin7A.
- From the previous step, we found that sin(7A) = sin(7A).
- Therefore, cosec7A = 1/sin(7A) = 1/sin(7A).
- Simplifying, we get cosec7A = 1.
5. Final answer:
- We found that sin7A = sin(7A) and cosec7A = 1.
- Therefore, sin7A cosec7A = sin(7A) * cosec7A = sin(7A) * 1 = sin(7A).
- Thus, the value of sin7A cosec7A is sin(7A).
- Since sin(7A) = sin(7A), the answer is Option C) 2.
If the value of sin A + cosec A = 2, then what is the value of sin7 A ...
It is given that sin A + cosec A = 2 ……(i)
On putting A = 900, then above condition will satisfy
sin 900 + cosec 900 = 2
or, 1 + 1 = 2 (as the equation satisfies, so, A = 900)
Now, sin7 A + cosec7 A = ?
⇒ sin7 900 + cosec7 900
⇒ 17 + 17
= 2