NDA2023MathematicsTrigonometric Ratios & IdentitiesActual
Paragraph: Given that x+ x+ x+ x+ x+ cosec x=7 Question: If 2 x=a-b c , where a and b are natural numbers and c is prime number, then what is the value of a - b +2 c ?
Options
- A0
- B14
- C21
- D28
Correct answer
D. 28
Step-by-step solution
2 x=a-b c ^2 2 x-44 2 x+36=0 2 x= 44 (44)^2-4(36) 2 = 44 4 11^2-9 2 =22 2 112 =22 8 7 2 x 1 2 x=22-8 7 =a-b c a=22, b=8, c=7a-b+2 c=22-8+14=28