Question

Express the following in the form of a+ib. "-
1.) (2-3i) (2-3i)
2.)(3+4i)(3-4i) ​

Answer 1

Answer:

1.)

Expanding (2-3i) (2-3i) , we get....

$= > {(2 - 3i)}^{2} \\ = > {(2)}^{2} - 2 \times 2 \times 3i + {(3i)}^{2} \\ = > 4 - 12i + 9 {i}^{2} \\ we \: know \: that \: {i}^{2} = - 1. \\ = > 4 - 12i + 9( - 1) \\ = > 4 - 12i - 9 \\ = > - 5 - 12i.$

2.)Expanding (3+4i)(3-4i), we get......

$= > (3 + 4i)(3 - 4i) \\ = > {(3)}^{2} - {(4i)}^{2} \\ = > 9 - 16 {i}^{2} \\ we \: know \: that \: {i}^{2} = - 1. \\ = > 9 - 16( - 1) \\ = > 9 + 16 \\ = > 25.$

Answer 2

Check the attachment :)