A.$\dfrac{{27}}{{512}};$

B. $\dfrac{{33}}{{528}};$

C. $\dfrac{{31}}{{528}};$

D. $\dfrac{{25}}{{512}}.$

A.$\dfrac{{41}}{{11}};$

B. $\dfrac{{32}}{9};$

C. $\dfrac{{42}}{{11}};$

D. $\dfrac{{31}}{9}.$

A.17;

B.153;

C.15,21;

D.0,10100100010000…(viết liên tiếp sau dấu phẩy các luỹ thừa của 10)

A.-4;

B.8;

C.0;

D.-8

A.-2;

B.$2 - 4\sqrt 5 ;$

C.2

D.$2 + 4\sqrt 5 .$

A.$\left| x \right| \ge x;$

B.$\left| x \right| \ge  - x;$

C.${\left| x \right|^2} \ge {x^2};$

D.$\left| {\left| x \right|} \right| = x$

A.$\left| {x - y} \right| = x - y$;

B.$\left| {x - y} \right| = \left| x \right| - \left| y \right|$;

C.$\left| {x + y} \right| = \left| x \right| + \left| y \right|$

D.$\left| {x + y} \right| = \left| x \right| - \left| y \right|$ nếu $x > 0 > y;\left| x \right| > \left| y \right|$