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Current time:0:00Total duration:1:10

Video transcript

a function f of X is plotted below highlight an interval where f of X is less than zero so f of X which is really being plotted on the vertical axis right over here X is the horizontal axis f of X being less than zero really means that the graph is below the x-axis so the graph the function is negative in this interval right over here and this interval over here so I could put this anywhere right over here or I could stick it anywhere right over here let me stick it right over here there we go got it right let's do a couple more so the function is plotted below highlight an interval where f of X is greater than zero so I could do this area right over here where the function is above the x-axis or I could do this area right over here where the function is goes way above the XS while it even goes off the off the page so let's stick it let's stick it right over here let's do one more so highlight an interval where f of X is greater than zero once again I can do this region right over here where the function is a below us above the x-axis or over here where it's above the x-axis I'll do it here just for fun there we go