Portfolio Issues
Portfolio Draft 1 – Due Feb 25
1. Cardinality of units.
(a) Process 1: Clarify the concepts of cardinality in your personal phrases. (Definitions zero.three.26 – zero.three.29)
(b) Process 2: Decide one of many following and use the definition of cardinality to show or disprove the assertion.
• Drawback A: Z and the set E of even pure numbers have the identical cardinality. • Drawback B: The intervals (three, 5) and (2,∞) have the identical cardinality.
2. Supremum and Infimum of units.
(a) Process 1: Clarify the concepts of bounds, supremum, and infimum in your personal phrases. (Definition 1.1.2 – 1.1.three)
(b) Process 2: Do one of many following.
• Drawback A: Let E = . Decide sup E and inf E and show your solutions.
• Drawback B: Show: If x < zero and A ⊂ R is bounded beneath then sup(xA) = x inf A
three. Properties of the actual line.
(a) Process 1: Choose a couple of of the particular properties of R we’ve talked about (Theorem 1.2.1, Archimedean Property, Q is dense in R, R is uncountable, cardinality of intervals in R, and so forth) and clarify what you perceive about them in your personal phrases. (e.g. What’s the property? Why is it attention-grabbing or helpful? and so forth)
(b) Process 2: Use the property that Q is dense in R to show one of many following. • Drawback A: Let a ∈ R and B = . Decide inf B and show your
reply.
• Drawback B: The set of irrational numbers is dense in R. That’s, between any two actual numbers x < y there may be an irrational quantity s in order that x < s < y.
four. Supremum and Infimum of capabilities.
(a) Process 1: Clarify what it means for a operate to be bounded and what the supremum and infimum of a operate is. (Def 1.three.6, Determine 1.three)
(b) Process 2: Full one of many following issues.
• Drawback A: Let f : D → R and g : D → R be bounded capabilities. Show that f + g : D → R is bounded and sup
x∈D (f + g) ≤ sup
x∈D f + sup
x∈D g.
• Drawback B: Let h : [−3, 2] → R be given by h(x) = 20 − x3 − x2 + 7x. Show that h is bounded and discover sup
x∈[−3,2] h and inf
x∈[−3,2] h.
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Recall the duties: For every studying goal college students will…
1. Clarify the idea in their very own phrases, offering footage and examples as applicable to exhibit their understanding.
2. Write an entire and polished proof or answer, chosen from a listing of issues.
three. Replicate on what they discovered in regards to the matter.
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