Question

tính nhanh

a. 2012 x 24 + 77 x 2012 - 2012

b. 3³ x 76 + 84 x 27 + 3² x 3 x 40

c. 2⁸³ + 2⁸⁴ + 2⁸⁵

  2⁸² + 2⁸¹ + 2⁸⁰

Answer 1

a, 2012 x 24 + 77 x 2012 - 2012 

= 2012 x (24 + 77  - 1)

= 2012 x 100

= 201 200

Answer 2

b, 3³ x 76 + 84 x 27 + 3² x 3 x 40

= 27 x 76 + 84 x 27 + 27 x 40

= 27 x (76 + 84 + 40)

= 27 x 200 

= 5400

Answer 3

c,

C =  \(\dfrac{2^{83}+2^{84}+2^{85}}{2^{82}+2^{81}+2^{80}}\)

C = \(\dfrac{2^{83}.\left(1+2+2^2\right)}{2^{80}\left(2^2+2+1\right)}\)

C = 2³ 

C = 8