there is , is continues in

point. i need to prove that

by epsilon delta definition.

i need to followmy books prove.help me understand it.only

the books proof:

in order to prove

we will use the definition that for

surrounding we have surrounding for which every

.

first step:

is continues in point. so

and for surrounding we have

surrounding for which every

.

second step:

it is given that then for

so .

cant understand this last step why

is the resolt of the last two steps??