Graph y=x^4 - 3x^2 + 2 & Find x-intercepts

[rachael]

Sketch the graph, labelling the x-intercepts with exact values

how do i work this equation out?

y=x^4 - 3x^2 + 2

 

[topsquark]

Sketch the graph, labelling the x-intercepts with exact values

how do i work this equation out?

y=x^4 - 3x^2 + 2

This equation is known as a "biquadratic." It factors. If it helps, set a=x^2 and take a look at it again.

-Dan

 

[rachael]

thank you
so the new equation would be
a^2 - 3a + 2
then use the rule 'completing the square'

 

[z-component]

You could factor it using synthetic division. Once you find its factors, you can plot the points, test for sign changes, and sketch it as usual.