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

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

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

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

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

256,23 + 12,56 = 268,79

56,23 + 12,45 = 68,68

89,67 - 23,45 = 66,22

1,23 + 34,67 = 35,9

19,56 + 45,65 = 65,21

kp voi : http://olm/thanhvien/gop123 va mih dj

28(29-23) - 29(28-23)

= 812-644-812+667

= 23

(-167).(67-34)-67.(34-167)

= -11189+5678-2278+11189

= 3400

28(29-23) - 29(28-23)

= 812-644-812+667

= 23

(-167).(67-34)-67.(34-167)

= -11189+5678-2278+11189

= 3400

=79

=90

\(67+12=79\)

\(67+23=90\)

hok tốt

Chọn B

Vì :

\(\sqrt{5,76}=2,4\\ \sqrt{0,25}=0,5\\ \sqrt{2,5}=\sqrt{\dfrac{5}{2}}\approx1,58...\)

23 x 67 +23 x 24 -23 = 23 x \(\left(67+34-1\right)\)=23x 100 = 2300

đúng nhé

mình chán tính nhanh lắm rùi bạn lấy máy tính casio bấm cho nhanh

23+45+34+67+89+14+67+69+34=442

23+45+34+67+89+14+67+69+34=442

23 + 67 = 90

23 + 78 = 101

90

101

nhé

\(=\dfrac{4\left(\dfrac{1}{11}+\dfrac{1}{121}-\dfrac{1}{12321}\right)}{9\left(\dfrac{1}{11}+\dfrac{1}{121}-\dfrac{1}{12321}\right)}=\dfrac{4}{9}\)