如何求导这四道题？？求大神

如下

(3)
y=(√x+1)^cosx
lny = cosx. ln(√x+1)
(1/y)y' = -sinx. ln(√x+1) + cosx. ( 1/[2√x. (√x+1)] )
= -sinx. ln(√x+1) + (1/2)[cosx/(x+√x)]
y' = { -sinx. ln(√x+1) + (1/2)[cosx/(x+√x)] } .(√x+1)^cosx
(4)
y =1/x + ln(lnx) + 3(tanx)^2
y' = -1/x^2 + 1/(xlnx) + 6(tanx) . (secx)^2
(5)
y= √(x-1) .(x+2) / [ e^x. (2x+1)^3 . (x+1)^(1/3) ]
lny = (1/2)ln(x-1) + ln(x+2) - 1 - 3ln(2x+1) - (1/3)ln(x+1)
(1/y)y' =(1/2)[1/(x-1)] + 1/(x+2) - 6/(2x+1) - (1/3)[1/(x+1)]
y'
= { (1/2)[1/(x-1)] + 1/(x+2) - 6/(2x+1) - (1/3)[1/(x+1)] } .y
= { (1/2)[1/(x-1)] + 1/(x+2) - 6/(2x+1) - (1/3)[1/(x+1)] }
.√(x-1) .(x+2) / [ e^x. (2x+1)^3 . (x+1)^(1/3) ]
(6)
y=2^x.cosx + √x.arcsinx
y' = [ -sinx + (ln2).cosx ]. 2^x + √x/√(1-x^2) + (1/2) [arcsinx/√x]