Question

What is the correct formula for the value of the determinant?
la bl
|c d|

Answer 1

C. ad - cb

Step-by-step explanation:

Answer 2

`D = ab - cd`

Step-by-step explanation:

Given

`\left[\begin{array}{cc}a&b\\c&d\end{array}\right]`

Required

Determine the determinant

Represent the determinant with D

Since the above matrices is 2 by 2.

All we have to do is to multiply the alternate elements of the columns

i.e. (a * d) and (b * c)

Then subtract:

`D = (a * d) - (b * c)`

Simplify

`D = (ad) - (bc)`

`D = ab - cd`