1)308:4x2=77x2=154
2) =35/56
3)A={5,6,7}
4) MN=(AB+CD)/2
(AB+CD)/2=15
AB+CD=15x2
AB+CD=30 cm
5)Aria laterala=perimetrul bazeix apotema/2
Pbazei=4xl=4x4cm=16cm
6)Mp=(5x2+6x5+7x8+8x6+9x4+10x3)/(2+5+8+6+4+3)=220/28=7,86
subiectl II
3) x-pretul initial
ieftinirea: x-20x/100=x-x/5=(5x-x)/5=4x/5
scumpire: 4x/5+20/100·(4x/5)=4x/5+4x/25=(20x+4x)/25=24x/25
24x/25=1152
x=(1152·25)/24
x=1200 lei pretul initial
4)f(x)=2x-4
a) f(0)=-4
f(1)=2·1-4=-2
f(2)=0
f(-1)=-6
si reprezinti
5)={[(x+1)(x+3)/(x-1)(x+3)]-2/(x+1)-7/(x-1)(x+1)}·(x²-1)=x²-4 simplificam cu x+3
{(x+1)/(x-1)-2/(x+1)-7/(x-1)(x+1)]·(x-1)(x+1)=x²-4 aducem la acelasi numitor
{[(x+1)(x+1)-2(x-1)-7]/(x-1)(x+1)·(x-1)(x+1)=x²-4 simplificam cu (x-1)(x+1)
x²+x+x+1-2x+2-7=x²-4
x²-4=x²-4
x²-x²=4-4
x∈Ф
