Contact us
Choose a category below so we can get back to you as quickly as possible.
∵|a-2b|+(b-3c)的平方=0, 又因為|a-2b|≥0且(b-3c)²;≥0 ∴a-2b=0,b-3c=0 得a=2b,b=3c ∴a=6c ∴a+b-2c=6c+3c-2c=7c
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.