00:01
An equation is linear if there is no multiplication of the variables or if there is no power.
00:12
Like if none of the variables are raised to any power, then that's when we know the equation is linear.
00:21
So let's first look at the first one, x1 plus 5x2 minus the square root of 2x3.
00:35
An equation is linear.
00:40
Alright, let's check to see if this is linear.
00:46
There is one thing in this question that makes it nonlinear, and it's this part, the square root.
00:55
So remember the square root is the same thing as writing x cubed to the half.
01:04
And linear equations are written in the form, for example, so it's off order 1, means it should not be raised to any power, so that's what makes that nonlinear.
01:31
Alright, let's look at the second one.
01:36
X1, so let me put nl for nonlinear.
01:50
One second, nl for nonlinear.
01:58
Alright, the second one.
01:59
X1 plus 3x2 plus x1x3 is equal to 2.
02:12
There's one thing that makes this nonlinear, and that's x1 times x3...