cho abc=2. TínhT bằng (a/ab+a+2)+(b/bc+b+1)+(2c/ac+2c+2) 15/07/2021 Bởi Autumn cho abc=2. TínhT bằng (a/ab+a+2)+(b/bc+b+1)+(2c/ac+2c+2)
`T=(a/(ab+a+2))+(b/(bc+b+1))+(2c/(ac+2c+2))` `⇔T=(a/(ab+a+abc))+b/(bc+b+1)+(2cb)/(2+2cb+2b)` `⇔T=(1)/(b+1+bc) +(b)/(bc+b+1)+(cb)/(bc+1+b)` `⇔T=(bc+b+1)/(bc+b+1)` `⇔T=1` Bình luận
Thay abc=2 vào ta được T=(a/ab+a+2)+(b/bc+b+1)+(2c/ac+2c+2) =(a/ab+a+abc)+(b/bc+b+1)+(2c/ac+2c+2) =(1/b+1+bc) +(b/bc+b+1)+(2cb/acb+2cb+2b) =(1/b+1+bc) +(b/bc+b+1)+(cb/bc+1+b) =(bc+b+1/bc+b+1)=1 Vậy T=1 Bình luận
`T=(a/(ab+a+2))+(b/(bc+b+1))+(2c/(ac+2c+2))`
`⇔T=(a/(ab+a+abc))+b/(bc+b+1)+(2cb)/(2+2cb+2b)`
`⇔T=(1)/(b+1+bc) +(b)/(bc+b+1)+(cb)/(bc+1+b)`
`⇔T=(bc+b+1)/(bc+b+1)`
`⇔T=1`
Thay abc=2 vào ta được
T=(a/ab+a+2)+(b/bc+b+1)+(2c/ac+2c+2)
=(a/ab+a+abc)+(b/bc+b+1)+(2c/ac+2c+2)
=(1/b+1+bc) +(b/bc+b+1)+(2cb/acb+2cb+2b)
=(1/b+1+bc) +(b/bc+b+1)+(cb/bc+1+b)
=(bc+b+1/bc+b+1)=1
Vậy T=1