Question

Cine ma ajuta la 6 si 7.Va rog mult dau coroanaa

Answer 1

6.
a)√48+√15*(2/√3-4/√5)+(√5-1)²=
    4√3+10√45/15-12√75/15+5-2√5+1=
    4√3+2√5-4√3+5-2√5+1=6
b)[(√2-√3)²+√24]*(√50)^-1
     [√2²-2√6+√3²+2√6]*(√50)^-1=
        5*1/√50=
        5*1/5√2=√2/2
c)√21+12√3+|3-2√3|-(√3+2)²
     2√3+3-3+2√3-3-4√3-4=-7
7. |x-3/2|<=3
       x-3/2<=3
          x<=9
         -x+3/2<=3
           -x+3<=6
           -x<=3
              x>=-3
      -3<=x<=9
        x∈{-3,-2,-1,1,2,3,4,5,6,7,8,9}
         A={-3,-2,-1,1,2,3,4,5,6,7,8,9}
    3x+8/2x-3∈Z
   2x-3 | 2x-3  (1)
   2x-3 | 3x+8  (2)
(1) inmultim relatia cu 3
(2) inmultin relatia cu 2
2x-3| 7
2x-3 trebuie sa apartina divizorilor lui 7
D7={-1,1,7,-7}
2x-3=1
2x=4
x=2
2x-3=-1
2x=-2
x=1
2x-3=7
x=5
2x-3=-7
x=-2
B={1,2,5,-2}
A∩B={1,2,5,-2}