Question

g(t)=t^4+2t^3 is concave up everywhere? T or F:

Answer 1

You may need the second derivative test - if the second derivative is positive for all x, then it's concave up for all x. So find f''(x)

Answer 2

ok..great tks

Answer 3

Second derivative will be \[\large f''(x)= 12t^2+12t = \] \[\large 12t(t+1)\]

Will that be positive for all t?