If (55 + x)/2 is to be 67, then 55+x = 2*67, so x = 2*67 - 55 = 79
5:50 —> divide by 5 so it becomes 1:10
: means to
The answer is i beleve 75+15n
First we use product rule
y=x^2lnx
dy/dx = x^2 d/dx (lnx) + lnx d/dx (x^2)
dy/dx = x^2 (1/x) + lnx (2x)
dy/dx = x + 2xlnx
now taking second derivative:
d2y/dx2 = 1 + 2[x (1/x) + lnx (1)]
d2y/dx2 = 1 + 2[1+lnx]
1+2+2lnx
3+2lnx is the answer
