Answer:
a) and b) δ = 0.01 works for both M= 500 and M=1000
c) We take δ = 1/4 = 0.25
d) we take δ = 1/40 = 0.025
Step-by-step explanation:
Approximately, [tex] \frac{\pi}{2} = 1.57079632 . [/tex] Lets evaluate tan²(x) in a truncated expression of this approximation
tan²(1) = 1.557² = 2.4255
tan²(1.5) = 14,1² = 198.85
tan²(1.57) = 1255² = 1255² = 1576947
Notice that this value clearly works for the 2 given values of M.
Lets work with [tex] \delta = 0.01 [/tex] , since it didnt work for 0.1
tan²( π/2-0.01) = 10000 >1000>500
tan²(π/2+0.01) = 10000 (tan is asymmetrical respect to π/2, but tan² therefore is symmetrical).
δ = 0.01 works for both cases.
c) Note that if |x-1| < δ, then |4x-4| = |4(x-1)| = 4|x-1| < 4δ, for any value ε>0, we can take δ = ε/4.
if ε = 1, then we take δ = 1/4.
d) If ε = 0.1, then we take δ = 0.1 /4 = 0.025
e) f(x) = 4x
for ε = 1, we may take x = 0.75 and x = 1.25
Note that f(1) = 4
f(0.75) = 3
|3-4| = 1
f(1.25) = 5
|5-4| = 1
For ε = 0.1, we take x = 0.975 and x = 1.025
f(0.975) = 0.975*4 = 3.9
f(1.025) = 4*1.025 = 4.1
In both cases, the difference is 0.1. Also, if you take values closer from 1, the difference will be smaller.