Bài tập
1) Thực hiện phép tính
a) 25 . 8 3 - 22 . 83 b) 54 - 2 . 53
c) ( 34 + 33) . ( 34 + 3)
92 d) 33. 22 - 33. 19
e) 24 . 5 - [ 131 - ( 13- 42) ] f) 508 . 609 - ( 223136 + 8916 ) : 69
2) Tìm x
a) 30- 5 . ( x - 3 ) = 5 b) 9 + 3 . x = 37 : 32 c)12 . ( x - 1 ) : 3 = 43 - 23
a) 25 . 8 3 - 22 . 83
\(=8^3.\left(25-22\right)=8^3.3=1536\)
b) 54 - 2 . 53
\(=5^3\left(5-2\right)=5^3.3=375\)
\(c,\frac{\left(3^4+3^3\right)\left(3^4+3\right)}{9^2}=\frac{108.84}{81}=112\)
d) 33. 22 - 33. 19
\(=3^3.\left(22-19\right)=3^3.3=3^4=81\)
e) 24 . 5 - [ 131 - ( 13- 42) ]
\(=80-\left(131+3\right)\)
\(=-54\)
2) Tìm x
a) 30- 5 . ( x - 3 ) = 5
\(5\left(x-3\right)=25\)
\(x-3=5\)
\(x=8\)
b) 9 + 3 . x = 37 : 32
\(9+3x=243\)
\(3x=234\)
x=78