Tổng tiền thưởng olm của em từ trước đến giờ là dưới 500 ngàn đồng ạ (7).

a) \(542=2.271\)

b) \(165=3.5.11\)

be - was/were - been.

become - became - become.

\(#NqHahh\)

\(C=\dfrac{1}{5.7}+\dfrac{1}{7.9}+...+\dfrac{1}{97.99}\)

\(C=\dfrac{1}{2}.\left(\dfrac{1}{5}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{9}+...+\dfrac{1}{97}-\dfrac{1}{99}\right)\)

\(C=\dfrac{1}{2}.\left(\dfrac{1}{5}-\dfrac{1}{99}\right)\)

\(C=\dfrac{1}{2}.\dfrac{94}{495}\)

\(C=\dfrac{47}{495}\)

\(#NqHahh\)

\(2^{2x-3}=32\)

\(2^{2x-3}=2^5\)

\(=>2x-3=5\)

\(2x=5+3\)

\(2x=8\)

\(x=8:2\)

\(x=4\)

Ta có:

\(100=2^2.5^2\)

\(200=2^3.5^2\)

\(120=2^3.3.5\)

\(BCNN\left(100;200;120\right)=2^3.3.5^2=8.3.25=600\)

Sửa đề:

Ta có:

\(100=2^2.5^2\)

\(200=2^3.5^2\)

\(300=2^2.3.5^2\)

\(BCNN\left(100;200;300\right)=2^3.3.5^2=600\)

\(#NqHahh\)

Ta có:

\(100=2^2.5^2\)

\(200=2^3.5^2\)

\(300=2^2.3.5^2\)

\(BCNN\left(100;200;300\right)=2^2.2^3.3.5^2=4.8.3.25=2400\)

\(#NqHahh\)

\(90+\left\{20-10+\left[12+78+\left(5^2-15\right)\right]\right\}\)

\(=90+\left\{20-10+\left[12+78+\left(25-15\right)\right]\right\}\)

\(=90+\left\{20-10+\left[12+78+10\right]\right\}\)

\(=90+\left\{20-10+\left[90+10\right]\right\}\)

\(=90+\left\{20-10+100\right\}\)

\(=90+\left\{10+100\right\}\)

\(=90+110\)

\(=200\)

\(#NqHahh\)

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