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Mathematics: explore STEM content (page 8 of 23) · openstem
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Mathematics
Algebra, calculus, proofs and statistics on openstem — flashcards, notes, quizzes and plots shared by the community. Study free, or clone anything into your library.
Adding up what you have Add every coin and bill one at a time. The order doesn't matter; the total comes out the same. Getting change Pay more than something costs and the shopkeeper gives back the difference. That's your change, and there
N is a subgroup of G such that gNg⁻¹ = N for every g ∈ G (equivalently, every left coset equals the corresponding right coset). Normal subgroups are precisely the kernels of group homomorphisms, and they allow the construction of the quotient group G/N.
Belief updating, written as arithmetic Bayes' theorem tells you how to revise a probability once evidence arrives. It's one equation. The denominator is just the law of total probability, summing both branches of the tree: The medical test,
Mathematics
Mathematics · L4 · Bayesian reasoning and Bayes' theorem
Similar: same shape, different size Two figures are similar when every pair of corresponding angles is equal AND every pair of corresponding sides is in the same ratio. That shared ratio is the scale factor. What the scale factor does Above
Mathematics
Mathematics · L2 · Scale Drawings & Similar Figures
Four relationships worth knowing on sight Spot the relationship and you can find a missing angle without measuring anything. Complementary and supplementary Vertical angles Two straight lines crossing make four angles in two matching pairs.
Three symbols, three answers Compare two numbers and only three things can be true: one is bigger, one is smaller, or they're the same. Comparing two-digit numbers Compare 52 and 58: both have 5 tens, so that's a tie. 58 has 8 ones and 52 o
What does it mean for an algorithm to run in O(n) time?
AIt always takes exactly n secondsBIts running time grows in direct proportion to the input size nCIt never depends on the input size at allDIt doubles the input size every step
Two kinds of series, two formulas Arithmetic series The trick behind it: pair the first term with the last, the second with the second-last, and so on. Every pair adds to the same total, and there are n/2 pairs. Worked, a concert hall. Fron
Distance and angle instead of across and up Cartesian coordinates locate a point by how far across and how far up. Polar coordinates use how far out and which way round. Read (r, θ) as: turn through θ, then go out a distance r. It's the nat
Four coins to know Penny, nickel, dime and quarter. Before you can add coins or make change, you need to look at one and know instantly which it is and what it's worth. Colour first, then size The penny is the only copper-coloured one, so i