1(a) $500 x (1+2%)25 x 12
= $500 x 1.0230
= $905.6807920516769
\(\approx\) $ 905.68
(b)(i)\(\quad(\frac{1+0.0339}{1})^1-1\\ = 0.0339\)
APR = 3.39%
(b)(ii) \(\quad (\frac{2+0.0329}{2})^2-1\\ = 0.033170602.....\)
APR = 3.32.....%
(b)(iii) \(\quad (\frac{4+0.0335}{4})^4-1\\ = 0.033923......\)
APR = 3.392.....%
(b)(iv) \(\quad (\frac{12+0.034}{12})^{12}-1\\=0.0345348......\)
APR = 3.45......%
Which of these gives the cheapest option when taking out a loan for two years?
3.29% p.a. compounded semi-annually.
How much interest would it cost to borrow $1,000 for two years under the cheapest option?
1000 x 3.32% x 2
= $66.4
(c) 1000 x (1+2.5%)4 x 10
= 1000 x 2.685063838
= $2685.1 approx.
(d) f(x) = 2 - 3ln(x) + 3x
\(f'(x)= \frac{3}{x}+3\\ f'(1)= \frac{3}{1}+3 = 6\)
f(x) = 2x2ex
\(f'(x)= 2xe^x(x+2)\\ f'(1)= 2(1)(e)(1+2)= 6e\)
g(x) = 1 + x2
\(g'(x)= 2x\\ g'(1)= 2(1)=2\)
(e) \(f(x)=x^3-2x^2-4x\\ f'(x)= 3x^2-4x-4\\ f''(x)= 6x-4\)
I don't know what's critical point and local maximum.......