X [-1; 0] en -2y [-2; 2] dan (x-2y) ^ 2 ...?

Antwoord:

# (x-2y) ^ 2 in 0,9 #.

Uitleg:

#x in -1,0 rArr -1lexle0 …………. << 1 >> #.

# -2y in -2,2 rArr -2le-2yle2 ………………. << 2 >> #.

#:. << 1 >> + << 2 >> rArr -1-2lex-2yle0 + 2, ie., #

# -3lex-2yle2 #.

#rArr (x-2y) in -3,2 = - 3,0 uu 0,2 #.

#rArr (x-2y) in -3,0 of, (x-2y) in 0,2 #.

# "If," (x-2y) in -3,0, -3le (x-2y) le0 #

# rArr0le (x-2y) ^ 2le9, of, #

# (x-2y) ^ 2 in 0,9 ……………………….. << 3 >> #.

# "Evenzo" (x-2y) in 0,2 rArr (x-2y) ^ 2 in 0,4 … << 4 >> #.

Het combineren #<<3,4>>#, we vinden,

# (x-2y) ^ 2 in 0,9 uu 0,4 #.

#rArr (x-2y) ^ 2 in 0,9 #.