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If i sin theta and -cos theta are the ro...

If `i sin theta and -cos theta` are the roots of the equation `ax^(2)-bx-c=0` where a,b, and c are the sides of a triangle ABC, then `cosB` is equal to

A

`1-(c)/(2a)`

B

`1-(c)/(a)`

C

`1+(c)/(2a)`

D

`1+(c)/(3a)`

Text Solution

Verified by Experts

The correct Answer is:
C
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AAKASH SERIES-PROPERTIES OF TRIANGLES-ADDITIONAL PRACTICE EXERCISE (LEVEL 1 (MAIN)) (Straight Objective Type Questions)
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