Question

1 vat sang AB co dang hinh mui ten dat vuong goc voi truc chinh cua TKHT cho anh ao cao 18cm cach TK 30cm. TK co tieu cu 15cm. Xac dinh vi tri va kich thuoc cua vat.

Answer 1

F’A’ = OF’ + OA’ = 15 + 30 = 45 cm

ΔF’A’B’~ΔF’OI

\(\Rightarrow\dfrac{F'A'}{F'O}=\dfrac{A'B'}{OI}\Rightarrow OI=...\)

Ta có: AB = OI = 6 cm

ΔOAB~ΔOA’B’\(\Rightarrow\dfrac{OA}{OA'}=\dfrac{AB}{A'B'}\Rightarrow OA=...\)