Q 26
pls provide the complete soln..
Attachments:
Answers
Answered by
2
cot70 + 4cos70 = x
cos70/ sin70 + 4cos70 = x
cos70 + 4cos70sin70 = x sin70 ...(1) ( taking sin70 as common denominator)
cos70 + 2sin140 =sin20 + 2sin40 = ( sin20 + sin40) +sin 40 = 2sin30cos10 +sin40
= cos10 + sin40 = sin80 + sin40 = 2sin60cos20 = √3sin70
from (1) ,
x= √3.
correct option is B
cos70/ sin70 + 4cos70 = x
cos70 + 4cos70sin70 = x sin70 ...(1) ( taking sin70 as common denominator)
cos70 + 2sin140 =sin20 + 2sin40 = ( sin20 + sin40) +sin 40 = 2sin30cos10 +sin40
= cos10 + sin40 = sin80 + sin40 = 2sin60cos20 = √3sin70
from (1) ,
x= √3.
correct option is B
Anonymous:
i do ..ty
Similar questions