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=Cách 1 (Đặt quý hiếm chung)Đặt = =>Mà xyz = 810 => 2k.3k.5k = 810 => ..." data-index="9" src="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-9-3đôi mươi.jpg?cb=1479474705" srcset="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-9-3trăng tròn.jpg?cb=1479474705 320w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-9-638.jpg?cb=1479474705 638w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-9-1024.jpg?cb=1479474705 1024w" sizes="100vw" loading="lazy" id="slide-image-8">
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vắt vào đề bài bác ta được:Hay =+..." data-index="11" src="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-11-3đôi mươi.jpg?cb=1479474705" srcset="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-11-3trăng tròn.jpg?cb=1479474705 320w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-11-638.jpg?cb=1479474705 638w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-11-1024.jpg?cb=1479474705 1024w" sizes="100vw" loading="lazy" id="slide-image-10">
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24(1+2y) = 18(1+4y)=>24 +48y = 18 +72yĐưa về 24y = 6 => y = chũm vào đề bài bác ta có=> = 18. => 18x = 90 => x = 5..." data-index="13" src="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-13-3đôi mươi.jpg?cb=1479474705" srcset="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-13-3trăng tròn.jpg?cb=1479474705 320w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-13-638.jpg?cb=1479474705 638w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-13-1024.jpg?cb=1479474705 1024w" sizes="100vw" loading="lazy" id="slide-image-12">
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 => =Bài 2: Cho tỉ lệ thành phần thức Chứng minc rằng (1)GIẢICách 1:Cách 2:= k => cố gắng vào 2 vế của (1) chứng..." data-index="16" src="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-16-3đôi mươi.jpg?cb=1479474705" srcset="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-16-3đôi mươi.jpg?cb=1479474705 320w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-16-638.jpg?cb=1479474705 638w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-16-1024.jpg?cb=1479474705 1024w" sizes="100vw" loading="lazy" id="slide-image-15">
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=Bài 4: Cho b2= ac; c2= bd. Chứng minh rằng:1)2)GIẢI1) VìVậy " data-index="18" src="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-18-3đôi mươi.jpg?cb=1479474705" srcset="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-18-320.jpg?cb=1479474705 320w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-18-638.jpg?cb=1479474705 638w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-18-1024.jpg?cb=1479474705 1024w" sizes="100vw" loading="lazy" id="slide-image-17">
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3 4 5a c ek= ..." data-index="28" src="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-28-3đôi mươi.jpg?cb=1479474705" srcset="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-28-3trăng tròn.jpg?cb=1479474705 320w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-28-638.jpg?cb=1479474705 638w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-28-1024.jpg?cb=1479474705 1024w" sizes="100vw" loading="lazy" id="slide-image-27">
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+ + + + +(vì chưng d>0)Mặt khác: ( )2a aa b c a b c d>+ + + + ++ Từ (1) cùng (2) ta có: ( )3a..." data-index="33" src="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-33-3đôi mươi.jpg?cb=1479474705" srcset="https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/85/cc-bi-ton-v-t-l-thc-33-3đôi mươi.jpg?cb=1479474705 320w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-33-638.jpg?cb=1479474705 638w, https://image.hanvietfoundation.orgcdn.com/ccbitonvtlthc-161118131113/95/cc-bi-ton-v-t-l-thc-33-1024.jpg?cb=1479474705 1024w" sizes="100vw" loading="lazy" id="slide-image-32">












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