mik ko bít
I don't now
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\(\Delta ABC\)là tam giác vuông. do \(\sqrt{AB^2+AC^2}=BC\)
a) tìm \(\widehat{C}\)
\(sinC=\frac{AB}{BC}=\frac{10}{26}=\frac{5}{13}\)
\(\Rightarrow\widehat{C}\approx23º\)
Tìm góc B: \(\widehat{B}=90º-\widehat{C}\approx90º-23º\approx67º\)
b) tìm AH
\(AH.BC=AB.AC\)
\(\Leftrightarrow AH.26=10.24\)
\(\Leftrightarrow AH=240:60=4cm\)
có j sai xót mong m.n bỏ qa