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I don't see a sigma symbol on the calculator.
If you mean ∑ from the insert menu, then yes, but that's for display only, not for calculating. If you mean in LaTeX, then yes, but, again, that's display only.
Answer to part 1.
E(x+y) = E(x) + E(y) = 1/2 + 1/2 = 1
Sorry Melody, will do!
h isn't in the denominator (on the right-hand side) in the last line, but I guess it would be better to write
$$\lim_{h\rightarrow 0}\frac{f(x+h)-f(x)}{h}=2x-6$$
I thought it would be of interest to find a non-calculus solution to this problem; so here is my attempt:
f(x+h) = (x+h)2 - 6(x+h) +8 = x2 + 2hx + h2 - 6x - 6h + 8 = x2 - 6x + 8 + h(2x - 6) + h2
f(x) = x2 - 6x + 8
f(x+h) - f(x) = h(2x - 6) + h2
(f(x+h) - f(x))/h = 2x - 6 + h
When h = 0 (f(x+h) - f(x))/h → 2x - 6
a = 6.9m/s2, t = 1s so d = (1/2)*6.9m/s2*1s2 = 3.45m
Yes, because it can be written as 33/10, the ratio of two whole numbers.
x2 + y2 = 16 is the equation of a circle of radius 4 centred on (0, 0)
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