http://apcentral.collegeboard.com/apc/public/repository/ap10_calculus_bc_scoring_guidelines.pdf #3 part C, how do you find t?

Question

campbell_st · Answer

just after a quick read... it the tangent is zero then the slope is zero... 

so the 1st derivative is zero... 

so find the value of  t that makes the 1st derivative zero... 

so you are looking for a stationary point... i.e. a max, min or horizontal point of inflexion

anonymous · Answer

So i should try to graph it on the calculator? and then pick one of those points?

campbell_st · Answer

well for mine they have used the chain rule to find dy/dx

and since 2t - 4 can't be zero... you can ignore othe than 

$$t \neq 2$$

so solve the numerator 

$$t e^{t -3} - 1 = 0$$

anonymous · Answer

ya that is correct solve the numerator

anonymous · Answer

t is not = 2