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Let f(x) = x4- 8x2 . find the relativeextrema of this function using the second derivative test.

Which is the best for showing percentages of different types of cars sold(gas hybrid , electric , other ) in the united states ?

Students design a model roller-coaster track. they place a rubber ball at the highest point on the track and let it go. the ball rolls along the track pulled only by the force of gravity. eventually, it comes to a stop. which change to the design will result in the ball moving the greatest distance?