Cho các hệ vectơ U ={(1;2;7);(0;-1;-6);(2;3;8);(1;0;-5 )} a) Tìm số chiều và cơ sở W của không gian con sinh bởi hệ vectơ U b) Tìm tham số K để U = (2;3;k²+1) là một tổ hợp tuyến tính của W và suy ra [U]w

The radical equation 2+√2x-3 = √x+7 has a solution set [x= a0} and an extraneous root x = a1.

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling

If private savings 'v' = 0.75s and total savings 's' equals $4.20 billion, solve for public and private savings.