\(B=tan^267^0-cot^223^0+2\cdot\left(sin^216^0+cos^216^0\right)-2\)

\(=0+2\cdot1-2=0\)

\(A=cot67\cdot tan67-2\left(\dfrac{\sqrt{2}}{2}\cdot sin64\right)^2-2\cdot\dfrac{sin23}{3\cdot sin23}-sin^226^0\)

\(=1-2\cdot\dfrac{1}{2}\cdot sin^264^0-\dfrac{2}{3}-sin^226^0\)

\(=1-1-\dfrac{2}{3}=-\dfrac{2}{3}\)

b. 0

c. 112

d. 1250

e. -78

f. -67

b) [(24+-67)]-[-67-(-24)]=0
c) 2^3.17-2^3.14=112
d) 26.(-125)-125.(-36)=1250
e) 48-6(12+9)=-78
f) (-67).(1-301)-301.67=-67

\(A=\frac{67^{2016}}{67^{2016}}-11=1-11=-10< 0\)

\(\Rightarrow A< 0\)

\(B=\frac{67^{2016}+3}{67^{2016}+2}>0\)

\(\Rightarrow B>0\)

Vậy \(B>A\)

Tính bằng cách thuận tiện nhất :

a. 67 x 126 - 67 x 84 - 41 x 67 - 67

= 67 x 126 - 67 x 84 - 41 x 67 - 67 x 1

= 67 ( 126 - 84 - 41 - 1 )

= 67 x 0

=0

b. 36 x 2 x 2 + 7 x 28

=  2 ( 36 x 2 + 14 x 7 )  

= 2 x 170

= 340

c. 24 x 18 + 12 x 64

= 12 x 2 x 18 + 12 x 64

= 12 ( 2 x 18 + 64)

= 12 x 100

= 1200

a. 67 x 126 - 67 x 84 - 41 x 67 - 67

= 67 x 126 - 67 x 84 - 41 x 67 - 67 x 1

= 67 ( 126 - 84 - 41 - 1 )

= 67 x 0

=0

b. 36 x 2 x 2 + 7 x 28

=  2 ( 36 x 2 + 14 x 7 )  

= 2 x 170

= 340

c. 24 x 18 + 12 x 64

= 12 x 2 x 18 + 12 x 64

= 12 ( 2 x 18 + 64)

= 12 x 100

= 1200

67x126-67x84-41x67-67

=67x126-67x84-41x67-67x1

=67x(126-84-41-1)

=67x0

=0

36x2x7+7x28

=2(36x2+14x7)

=2x170

=340

24x18+12x64

=12x2x18+12x64

=12(2x18+64)

=12x100

=1200

= 167 x 67 + 167 x 30 + 161 x 1 + 167 x 2 

= 167 x (67 +30 +1 + 2 )

=167 X 100

= 16 700

Ta có:

\(A=\frac{67^{2016}}{67^{2016}-11}=1+\frac{11}{67^{2016}-11}\)

\(B=\frac{67^{2016}+13}{67^{2016}+2}=1+\frac{11}{67^{2016}+2}\)

Vì \(67^{2016}-11< 67^{2016}+2\) nên \(\frac{11}{67^{2016}-11}>\frac{11}{67^{2016}+2}\Rightarrow1+\frac{11}{67^{2016}-11}>1+\frac{11}{67^{2016}+2}\)

Vậy A > B 

25 x 67 x 4 = ( 25 x 4) x 67 = 100 x 67 = 6700

125 x 2 x 4 = ( 125 x 4) x 2 = 500 x 2 = 1000

67 x 5 x 2 = 67 x ( 5x2) = 67 x 10 = 670

50 x 78 x 2= ( 50 x 2) x 78 = 100 x78 = 7800

25 x 67 x 4 = (25 x 4) x 67 = 100 x 67 = 6700

125 x 2 x 4 = ( 125 x 4 ) x 2 = 500 x 2 = 1000

67 x 5 x 2 = 67 x ( 5 x 2) = 67 x 10 = 670

50 x 78 x 2 = ( 50 x 2 ) x 78 = 100 x 78 = 7800

25x4x67=6700

125x2x4=1000

67x(5x2)=670

50x2x78=7800

\(\dfrac{2}{67}-\left(\dfrac{3}{7}+\dfrac{2}{67}\right)\\ =\dfrac{2}{67}-\dfrac{215}{469}\\ =\dfrac{-3}{7}\)

\(\dfrac{3}{4}.\dfrac{5}{2}+\dfrac{5}{4}.\dfrac{5}{2}\\ =\left(\dfrac{3}{4}+\dfrac{5}{4}\right).\dfrac{5}{2}\\ =2.\dfrac{5}{2}\\ =\dfrac{5}{1}\)

a)

=67.(36+65-1)

=67.100

=6700

b)

=[7²³.(45+4)]:7²⁵

=[7²³.    49   ]:7²⁵

=[7²³.    7²   ]:7²⁵

=7²⁵     :7²⁵

=1

a) 67.36 + 67.65 - 67 = 67.\(\left(36+65-1\right)\) = 67. 100 = 6700

b) \(\left(7^{23}.45+7^{23}.4\right):7^{25}\) = \(7^{23}.\left(45+4\right):7^{25}=7^{23}.7^2:7^{25}=1\)