CALCULATI:
a. 1supra9+2supra3ori(1supra4-1supra6)
b. 3supra10-2supra5ori(7supra10-1supra5)
c. 4supra5ori[1supra2+1supra2ori(1supra2-1supra4)]
d. [1 unu supra trei-2supra3ori(5supra6+1supra3)]ori 3supra10
Răspunsuri la întrebare
a. 1/9 + 2/3 * (1/4 - 1/6) =
= 1/9 +2/3 * (3/12 - 2/12) =
= 1/9 +2/3 * 1/12 =
= 1/9 + 1/18 =
= 2/18 + 1/18 =
= 3/18 = 1/6
b. 3/10 - 3/5 * (7/10 - 1/5) =
= 3/10 - 3/5 * (7/10 - 2/10) =
= 3/10 - 3/5 * 5/10 =
= 3/10 - 3/10 = 0
c. 4/5 * [1/2 + 1/2 * (1/2 - 1/4)] =
= 4/5 * [1/2 + 1/2 * (2/4 - 1/4)] =
= 4/5 * (1/2 + 1/2 * 1/4) =
= 4/5 * (1/2 + 1/8) =
= 4/5 * (4/8 + 1/8) =
= 4/5 * 5/8 =
= 1/2
d. [1/3 - 2/3 * (5/6 + 1/3)] * 3/10 =
= [1/3 - 2/3 * (5/6 + 2/6)] * 3/10 =
= (1/3 - 2/3 * 7/6) * 3/10 =
= (1/3 - 7/9) * 3/10 =
= (3/9 - 7/9) * 3/10 =
= (-4/9) * 3/10 =
= -2/15
Răspuns:
Explicație pas cu pas:
a.
1/9 + 2/3 × ( 1/4 - 1/6 ) = 1/6
= 1/9 + 2/3 × ( 3/12 - 2/12 ) =
= 1/9 + 2/3 × 1/12 =
= 1/9 + 1/18 =
= 2/18 + 1/18 =
= 3/18 =
= 1/6
_______________________________
b.
3/10 - 2/5 × ( 7/10 - 1/5 ) = 1/10
= 3/10 - 2/5 × ( 7/10 - 2/10 ) =
= 3/10 - 2/5 × 5/10 =
= 3/10 - 1/5 =
= 3/10 - 2/10 =
= 1/10
_________________________
c.
4/5 × [ 1/2 + 1/2 × ( 1/2 - 1/4 ) ] = 1/2
= 4/5 × [ 1/2 + 1/2 × ( 2/4 - 1/4 ) ] =
= 4/5 × ( 1/2 + 1/2 × 1/4 ) =
= 4/5 × ( 1/2 + 1/8 ) =
= 4/5 × ( 4/8 + 1/8) =
= ( 4/5 ) × ( 5/8 ) =
= 1/2
________________________
d.
[ 1/3 - 2/3 × ( 5/6 + 1/3 ) ] × 3/10 = - 2/15
= [ 1/3 - 2/3 × ( 5/6 + 2/6 ) ] × 3/10 =
= ( 1/3 - 2/3 × 7/6 ) × 3/10 =
= ( 1/3 - 7/9 ) × 3/10 =
= ( 3/9 - 7/9 ) × 3/10 =
= ( - 4/9 ) × 3/10 =
= - 2/15