Sequences and Nth Terms
Example: 2, 5, 8, 11, ... might be an = 3n-1. Index n usually starts at 1 in school. Recurrence: a{n+1} from a_n (later AP/GP).
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Example: 2, 5, 8, 11, ... might be an = 3n-1. Index n usually starts at 1 in school. Recurrence: a{n+1} from a_n (later AP/GP).
This topic compares the electrical behaviour of conductors and insulators.
A model simplifies a real system so predictions can be made, but every model has limits.
Angina Pectoris: Angina pectoris is occasional chest pain that occurs when the heart muscle does not receive enough oxygen. It is most likely to occur when…
Variation refers to the differences in traits among members of the same species. It is the raw material for evolution. Variations arise from meiosis (crossing…
Atmosphere The envelope of gases and water vapour surrounding the planet Earth is called the atmosphere. Simple explanation: The atmosphere is…
One-to-one (injective): different inputs -> different outputs. Onto (surjective): every element of the stated codomain is hit. Bijective: both, so an inverse…
Carboxylic Acids: Carboxylic acids are organic compounds that contain the carboxyl group (-COOH) attached to a hydrocarbon chain. General Formula:…
The determinant is a single number attached to a square matrix. 2x2: det [[a,b],[c,d]] = ad-bc. 3x3: expand along a row or column using cofactors. Cofactor…
The main idea is that the carboxyl group shows the chemistry of both the carbonyl (C=O) and the hydroxyl (-OH) groups. In most reactions, the carboxyl…
A metallic bond is a strong electrostatic attraction between a cloud/sea of delocalized electrons and positively charged cations. Simple…
Three non-collinear points lie on exactly one circle (their circumcircle). Three collinear points do not determine a circle. The centre is the meeting of the…
Only use secure websites with URLs beginning with "https://" and a padlock symbol when making purchases or sending money online. Take care not to divulge…
Phosphodiester Bond: A phosphodiester bond is a covalent bond that links two nucleotides together in a polynucleotide chain. It forms between the phosphate…
The heart chambers are the four hollow spaces within the heart that receive and pump blood. They are: 1. Right atrium — receives deoxygenated blood…
Biochemistry is the study of the chemical compounds and chemical processes within living organisms. It bridges biology and chemistry, using chemical knowledge…
A survey is a systematic or structured tool designed for data collection from a group of individuals. Usually, surveys are conducted through printed…
If the centre is known: join OP, draw the circle on OP as diameter, meet the given circle again at T (angle in a semicircle is 90, so OT perp PT). Then PT is…
Alcohol + carboxylic acid <-> ester + water, acid catalyst (conc H2SO4 named), heat. Reversible (equilibrium chapter idea). Name: alkyl from the alcohol +…
-1 <= sin(anything) <= 1. Multiply by 7: -7 to 7. a + b sin theta: [a-|b|, a+|b|]. Shift then stretch.
Infections that can spread through sexual contact are named in the syllabus (HIV, hepatitis B, gonorrhoea, syphilis, HPV as the book lists). This page is…
A conic is defined by a focus-directrix ratio e; ellipse has e<1, parabola e=1, hyperbola e>1.
Biochemistry: Biochemistry is the study of the composition and structure of different chemical compounds found in living organisms and the chemical…
IUPAC nomenclature is a systematic method of naming organic compounds so that a compound can be identified from its name and chemists can communicate without…