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3. Multiplying complex numbers example ( Enter your problem )

1. Example-1





1. `A=5+6i,B=-2+3i,C=1-3i`
Find A × B


Solution:
Here `A=5+6i,B=-2+3i,C=1-3i`


`A * B`

`=(5+6i)*(-2+3i)`

`=5(-2)+5(3i)+6i(-2)+6i(3i)`

`=-10+15i-12i+18i^2`

`=-10+15i-12i+18(-1) ("Where " i^2=-1)`

`=-10+15i-12i-18`

`=-10-18+15i-12i`

`=-28+3i`
2. `A=5+6i,B=-2+3i,C=1-3i`
Find B × C


Solution:
Here `A=5+6i,B=-2+3i,C=1-3i`


`B * C`

`=(-2+3i)*(1-3i)`

`=-2(1)-2(-3i)+3i(1)+3i(-3i)`

`=-2+6i+3i-9i^2`

`=-2+6i+3i-9(-1) ("Where " i^2=-1)`

`=-2+6i+3i+9`

`=-2+9+6i+3i`

`=7+9i`
3. `A=5+6i,B=-2+3i,C=1-3i`
Find A × C


Solution:
Here `A=5+6i,B=-2+3i,C=1-3i`


`A * C`

`=(5+6i)*(1-3i)`

`=5(1)+5(-3i)+6i(1)+6i(-3i)`

`=5-15i+6i-18i^2`

`=5-15i+6i-18(-1) ("Where " i^2=-1)`

`=5-15i+6i+18`

`=5+18-15i+6i`

`=23-9i`
4. `A=5+6i,B=-2+3i,C=1-3i`
Find 3×A


Solution:
Here `A=5+6i,B=-2+3i,C=1-3i`


`3 * A`

`=(3)*(5+6i)`

`=3(5)+3(6i)`

`=15+18i`
5. `A=5+6i,B=-2+3i,C=1-3i`
Find 2×B


Solution:
Here `A=5+6i,B=-2+3i,C=1-3i`


`2 * B`

`=(2)*(-2+3i)`

`=2(-2)+2(3i)`

`=-4+6i`




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