
Let's Solve ~





or


[ it's similar to expression - a² + 2ab + b² that is equal to (a + b)² ]
so, let's use this identity here to factorise :

I hope it was helpful ~
The maximum volume would be when the bottom of the box is a square.
The perimeter of the bottom is 36, so the side of the square would be 36/4 = 9 cm.
Then to find volume multiply the length by the width by the height:
Volume = 9 x 9 x 4 = 324 cm^3
The answer would be a.
Y = t*e^(-t/2)
y' = t' [e^(-t/2)] + t [e^(-t/2)]' = e^(-t/2) + t[e^(-t/2)][-1/2]=
y' = [e^(-t/2)] [1 - t/2] = (1/2)[e^(-t/2)] [2 - t] = - (1/2) [e^-t/2)] [t -2]