Example 1 Let a,b,c be positive real numbers, find a+2b+ca+3c+a+b+2c4b−a+b+3c8c
the minimum value.
A number or a short expression. Spacing and $ signs are ignored.
Solution
None
Translate the text above into English, please retain the original text's line breaks and format, and output the translation result directly.
Note: The provided instruction is a meta-instruction and not part of the text to be translated. Since the text to be translated is "None", the translation is also "None". Here is the formatted output as requested:
None
Want a route through all this instead of an archive? The track
puts 2,000 problems in a working order, from AMC 10 level to the IMO shortlist.
Source: NuminaMath-1.5,
licensed Apache-2.0.
Statement and solution reproduced as published; topic and difficulty added by this site.