Q. The principal of i i is equal to - a . e b . e - π / 2 c . e - 3 π / 2 d . n o n e o f t h e s e Explain stepwise with formulas if any. Share with your friends Share 0 Neha Sethi answered this Dear student Sometimes according to the need of the answer, we make the requiredsubstitutions.If we will put x=0 in, eix=cosx+isinx⇒ei0=cos0+isin0⇒e0=1+0⇒1=1 as e0=1but this will not lead to any conclusion.Again if we put x=π3 in, eix=cosx+isinx⇒ eiπ3=cosπ3+isinπ3⇒eiπ3=12+i32Again this will not lead to any conclusion.But if we put x=π2 in, eix=cosx+isinx⇒ eiπ2=cosπ2+isinπ2⇒eiπ2=0+1i⇒i=eiπ2This way we are able to proceed and will get the desried result. Regards 1 View Full Answer