Li Jiaxing didn’t even think about it，Happily signed the name on it。
“alright，You let go。”Qiao Tianyu waved，Coaxed Li Jiaxing from his seat。
He sat down，I picked up the paper, pen and brush to write，“A cup of black coffee，Thick，Thank you！”
“Hey Hey hey，what are you doing？”Li Jiaxing’s second-born monk can’t figure it out。
“Write a proof of Fermat’s last theorem！”
Qiao Tianyu threw a meaningful smile at Li Jiaxing，Then he bowed his head and continued to write the proof。
“joke！”Li Jiaxing murmured a little。
“If you can prove Fermat’s last theorem，I can call you grandpa！”
After speaking, Li Jiaxing took the draft paper and went to another table to prove it.。
“Hi hi hi，grandson！”Three hours later，Qiao Tianyu photographed a stack of draft papers in front of Li Jiaxing，“Come，Call grandpa！”
“What grandpa？！”
Li Jiaxing gave Qiao Tianyu a white look，Lower your head and start studying Qiao Tianyu’s proof process。
Qiao Tianyu knows this proof process，I can’t finish it in three or five hours，Li Jiaxing stayed，Went out to find a place to eat。
Busy for most of the day，I’ve already sang the empty city plan。
More than an hour later，Qiao Tianyu, who was full of food and drink, returned to the research room with a bag of fried chicken burgers。