không có biết

giúp j??

\(26,\\ a,\sin45^0=\cos45^0< \sin50^025'< \sin57^048'=\cos32^012'< \sin72^0=\cos18^0< \sin75^0\\ b,\tan37^026'< \tan47^0< \tan58^0=\cot32^0< \tan63^0< \tan66^019'=\cot23^041'\\ 27,\\ A=\dfrac{\left(\sin^226^0+\sin^264^0\right)+2\left(\cos^215^0+\cos^275^0\right)}{\left(\sin^255^0+\cos^255^0\right)+\left(\sin^242^0+\cos^242^0\right)}-\dfrac{\tan81^0}{2\tan81^0}\\ A=\dfrac{\left(\sin^226^0+\cos^226^0\right)+2\left(\sin^215^0+\cos^215^0\right)}{1+1}-\dfrac{1}{2}\\ A=\dfrac{1+2}{2}-\dfrac{1}{2}=2-\dfrac{1}{2}=\dfrac{3}{2}\)

\(28,\\ \sin^2\alpha=1-\cos^2\alpha=1-\dfrac{1}{2}=\dfrac{1}{2}\\ \Leftrightarrow\sin\alpha=\dfrac{\sqrt{2}}{2}\)

MIK CŨNG HỌC LỚP 6 NHƯNG MIK NGHĨ LÀ MIK CHƯA HỌC BÀI NÀY

Bài làm

Bạn hamlon bên dưới không làm được vậy để mình làm cho bạn .

\(\frac{3}{5}.\frac{3}{7}+\frac{3}{5}.\frac{2}{9}-\frac{3}{5}.\frac{3}{11}\)

\(=\frac{3}{5}\left(\frac{3}{7}+\frac{2}{9}-\frac{3}{11}\right)\)

\(=\frac{3}{5}.\left(\frac{297}{693}+\frac{154}{693}-\frac{189}{693}\right)\)

\(=\frac{3}{5}.\frac{262}{693}\)

\(=\frac{262}{1155}\)

vg tui ngu lam ban gioi,ban van minh,lich su lam co

4 cry a lot anymore

5 used to study at this school

6 used to walk to school

7 is a famous singer

8 have very long hair anymore

9 used to be good boys

10 used to get up early

11 work on a farm anymore

12 take much morning exercises anymore

13 use to smoke a lot

14 use to spend a lot of money