Answer: It's the second option
Step-by-step explanation:
Answer:
Step-by-step explanation:
Identities : -
cot = cos / sin
tan = sin / cos
( cot + tan ) sin = sec
LHS
= ( cot + tan ) sin
= ( ( cos / sin ) + ( sin / cos ) ) sin
= ( ( cos sin ) / sin ) + ( sin² / cos )
= cos + ( sin² / cos )
LCM = cos
= ( cos² / cos ) + ( sin² / cos )
= ( cos² + sin² ) / cos
Identity : -
cos² + sin² = 1
= 1 / cos
= sec
= RHS
Hence proved.
Answer:
20.
Given, complex number is 10+5i .
We need to find sum of the given complex number and its conjugate. The conjugate of 10+5i is 10-5i. Therefore, the sum will be 10+5i+10−5i=20.
