- Home
- Standard 11
- Mathematics
4-1.Complex numbers
easy
The values of $x$ and $y$ for which the numbers $3 + i{x^2}y$ and ${x^2} + y + 4i$ are conjugate complex can be
A
$( - 2, - 1)$or $(2, - 1)$
B
$( - 1,{\rm{ }}2)$or $( - 2,{\rm{ }}1)$
C
$(1,\,2)$or $( - 1, - 2)$
D
None of these
Solution
(a) According to condition, $3 – i{x^2}y = {x^2} + y + 4i$
$⇒$ ${x^2} + y = 3$and ${x^2}y = – 4$ $⇒$ $x = \pm 2,y = – 1$
$⇒$ $(x,y) = (2, – 1)$or $( – 2, – 1)$
Standard 11
Mathematics