\(B=\dfrac{1}{2}y+\dfrac{3}{4}\cdot\left|2y-1\right|-\dfrac{3}{2}\)
=1/2y-3/2+3/4(1-2y)(y<=1/2)
=1/2y-3/2+3/4-3/2y
=-y-3/4
Lời giải:
$B=\frac{y}{2}+\frac{3}{4}\sqrt{(2y-1)^2}-\frac{3}{2}$
$=\frac{y}{2}+\frac{3}{4}|2y-1|-\frac{3}{2}$
$=\frac{y}{2}+\frac{3}{4}(1-2y)-\frac{3}{2}$ (do $2y-1\leq 0$)
$=-(\frac{3}{4}+y)