Can someone help with this pls!! Thank u!

Answer:
(a+bi)×(b+ai)
=>ab+a²i+b²i+abi²
=> ab+(-1)ab+(a²+b²)i
=>(a²+b²)i
so we can say it is purely imaginary number
hope it helped!
Answer:
(a+bi)×(b+ai)
=>ab+a²i+b²i+abi²
=> ab+(-1)ab+(a²+b²)i
=>(a²+b²)i
Step-by-step explanation: