Thực hiện phép tính a) 2/5 + 3/5 : (-3/2) + 1/2; b) 2 1/2 + (-1/3)^2 - 3/2

a) 25+35:−32+12

=25+35.−23+12

=25+−25+12

=0+12=12

b) 212+−132−32

=52+19−32

=4218+218−2718=1718.

c) 78−0,25:56−0,752

=78−14:56−342

=78−14:56−342

=78−28:1012−9122

=58:1122=58:12122=58.122=5.1448=90.

 

d) −0,75−−2+32:1,5+−54

=−34−−42+32:32+−54

=−34−−12:32+−54

=−34−−12:32+−54

=−34+13+−54

=−34+−54+13

=−84+13

=−2412+412

=−2012=−53