微积分I(标准路径) · 免费预览
§1.7 Limits, continuity, and differentiability (continued)
从图象上看,说当 $x \to a$ 时 $f$ 有极限 $L$ 是什么意思?这与 $f$ 在 $x = a$ 处有左极限和右极限有什么联系?
1. Summary
Summary
2. The derivative of a piecewise linear function
A function is built from five straight-line segments with slopes , , , , and left to right, joined with corners, a jump at , and a missing value at . What does the graph of look like?
3. Cataloging failures on a piecewise linear graph
For the same : the two sides at approach and , the value does not exist, and the graph has corner points at , , and . Where is discontinuous, and where not differentiable?
4. Reasoning backward from a derivative graph
A function has a derivative whose graph is piecewise constant with values , undefined at . What can be concluded about ?
5. A cusp with a vertical tangent
Let . What happens to the difference quotient as approaches ?
6. An impossible combination
Which function is differentiable at but has no limit at ?
7. A limit that ignores a misplaced value
Let for every , with . What is true at ?
8. A cusp quotient at a sample point
For , evaluate the difference quotient value , rounded to three decimals.
9. The other side of the cusp
For the same , evaluate , rounded to two decimals.
10. Continuous everywhere yet not differentiable somewhere
A function can be continuous at every point and still fail to be differentiable at some point.