show that 5-2i/3+i + 5+2i /3-i is real no.
Answers
Answered by
0
Step-by-step explanation:
distribute the brackets using FOIL( or any method you use)
(
5
−
2
i
)
(
5
+
2
i
)
=
25
+
10
i
−
10
i
−
4
i
2
[ this process is useful in complex numbers as the product produces a real number - the 2nd bracket is the complex conjugate of the 1st and vice-versa.]
[ note :
i
2
=
(
√
−
1
)
2
=
−
1
]
⇒
(
5
−
2
i
)
(
5
+
2
i
)
=
25
+
10
i
−
10
i
+
4
=
29
a real number
Similar questions