Question

几条有关limit的数学题Find the value of c so that f(x) is continuous

Answer 1

1:用等价无穷小：lim f(x)=sin(3x)+e^(3cx) -1=3x+3cx=x(3+3c)

3+3c=1得c=-2/3

2:f(a) = 3a/(|a|+2a) a≠0

lim f(a)=3a/3a=1

lim f(a)=3a/a=3

lim f(a)≠lim f(a)≠f(0)

limit of x tend to 0 这里没有x,是a趋于0吧?这时极限不存在