Tardigrade
Tardigrade - CET NEET JEE Exam App
Exams
Login
Signup
Tardigrade
Question
Mathematics
If ((1+i)2/2-i)=x+iy, then x+y is equal to
Q. If
2
−
i
(
1
+
i
)
2
=
x
+
i
y
,
then
x
+
y
is equal to
1864
240
J & K CET
J & K CET 2007
Complex Numbers and Quadratic Equations
Report Error
A
−
5
2
25%
B
5
6
16%
C
5
2
47%
D
−
5
6
12%
Solution:
Given that,
2
−
i
(
1
+
i
)
2
=
x
+
i
y
⇒
2
−
i
1
+
i
2
+
2
i
=
x
+
i
y
⇒
2
−
i
1
−
1
+
2
i
=
x
+
i
y
⇒
2
−
i
2
i
×
2
+
i
2
+
i
=
x
+
i
y
⇒
(
2
)
2
+
(
i
)
2
2
i
(
2
+
i
)
=
x
+
i
y
⇒
5
4
i
−
2
=
x
+
i
y
⇒
x
+
i
y
=
−
5
2
+
5
4
i
Now,
x
+
y
=
−
5
2
+
5
4
=
5
2