1. Phải là 1

2 .Lẽ ra 63+23=86

3.lẽ ra 50+70=120

lp bn xàm vãi!!!

37x38+63x37-37

=37x ( 38+63-37 )

=37 x 64

=2368

Ta có :M=\(\frac{2012^{37}+37^{2012}+1}{2012^{38}}\)=\(\frac{1}{2012}\)+\(\frac{37^{2012}}{2018^{38}}\)+\(\frac{1}{2012^{38}}\)

N=\(\frac{2012^{38}+37^{2012}+2}{2012^{39}}\)=\(\frac{1}{2012}\)+\(\frac{37^{2012}}{2012^{39}}\)+\(\frac{2}{2012^{39}}\)

Suy ra: M-N=\(\frac{37^{2012}}{2012^{38}}\left(1-\frac{1}{2012}\right)\)+\(\frac{1}{2012^{38}}\left(1-\frac{2}{2012}\right)\)

\(\Rightarrow\)M-N=\(\frac{37^{2012}}{2012^{38}}.\frac{2011}{2012}+\frac{1}{2012^{38}}.\frac{2010}{2012}\)

\(\Rightarrow\)M-N>0

\(\Rightarrow\)M>N

Vậy M>N

a/(15+37)+(52-37-17)=15+37+52-37-17=50

b/(38-42+14)-(38-42-15)=38-42+14-38+42+15=29

15 + 37 + 52 - 37 - 17
= 15 + 37 - 37 + 52 - 17
= 15 + 0 + 52 - 17
= 67 - 17
= 50

b) 38 - 42 + 14 - 38 + 42 + 15
= 38 -38 + 42 - 42 + 14 + 15
= 0 + 0 + 14 + 15
= 29

A = 37³⁸+5/37³⁹+5 < 37³⁸+5+32 / 37³⁹+5+32

                            = 37³⁸+37 / 37³⁹⁺³⁷

                                  = 37(37³⁷+1) / 37(37³⁸+1)

                            = 37³⁷ + 1 / 37³⁸+1   = B

=> A < B nha!

Ai k mk mk k lại !!