Question

Tìm tất cả các phân số có tử là 15 và lớn hơn 3\7,nhỏ hơn 5\8

Answer 1

Ta có:

\(\dfrac{3}{7}\)=\(\dfrac{15}{35}\);\(\dfrac{5}{8}\)=\(\dfrac{15}{24}\)

Lại có:\(\dfrac{15}{35}\)<x<\(\dfrac{15}{24}\)

Vậy x={\(\dfrac{15}{34}\);\(\dfrac{15}{33}\).....;\(\dfrac{15}{25}\)}

Answer 2

gọi p/s cần tìm là a

ta có :

\(\dfrac{3}{7}\)< a <\(\dfrac{5}{8}\)

=> \(\dfrac{15}{35}\)<a<\(\dfrac{15}{24}\)

=> a \(\in\)\(\left\{\dfrac{15}{34};\dfrac{15}{33};...;\dfrac{15}{25}\right\}\)

Answer 3

gọi phân số cần tìm là a

\(\dfrac{3}{7}\)< a <\(\dfrac{5}{8}\)

\(\dfrac{5}{8}\)= \(\dfrac{15}{24}\)

\(\dfrac{3}{7}\)= \(\dfrac{15}{21}\)

=> \(\dfrac{15}{21}\)<a<\(\dfrac{15}{24}\)

=> a\(\in\) \(\left\{\dfrac{15}{22};\dfrac{15}{23}\right\}\)

Answer 4

x \(\in\) \(\left\{\dfrac{15}{34};\dfrac{15}{33};\dfrac{15}{32};...;\dfrac{15}{25}\right\}\)

nhá like cho mk đó