Lost Vocabulary

While reading the Victorian maths textbook 'Elementary Algebra for Schools' I spotted quite a few words together with phrases which are rarely used inward modern secondary schools. I'm non proverb that this vocabulary has disappeared from the plain of mathematics, but I incertitude you lot volition listen these price inward GCSE lessons.

Let's accept a quick hold off at about interesting words together with how they were used inward the 1800s.

Unity
Meaning (in this context): the number one.

• "When the coefficient is unity it is commonly omitted. Thus nosotros create non write 1a, but only a".
• "If the production of 2 quantities live on equal to unity, each is said to live on the reciprocal of each other".
• "Subtract 3x² - 5x + 1 from unity, together with add together 5x² - 6x to the result".
• "We continue right away to the resolution into factors of trinomial expressions when the coefficient of the highest ability is non unity".

Resolve into Factors
Meaning: factorise (UK) or cistron (US) - run across Colin Beveridge's post 'Factorise or Factor'.

• "Resolve into factors x² - ax + 5x - 5a".
• "The beginner should live on careful non to laid out cancelling until he has expressed both numerator together with denominator inward the nearly convenient form, past times resolution into factors where necessary". 
• "Resolve 4a²(x³+18ab²) - (32a⁵+9b²a³)  into 4 factors". 

Diminished
Meaning: made smaller or less.

• "The total of -3x, -5x, -7x, -x is -16x. For a total of coin diminished successively past times £3, £5, £7 together with £1 is diminished altogether past times £16".
• "Divide 105 into 2 parts, 1 of which diminished past times twenty shall live on equal to the other diminished past times 15".

Whence
Meaning: every bit a number of which.

• "Whence the final result follows".
• "Whence x = 1 is the exclusively solution"

Involution
Meaning: multiplying an aspect past times itself.

Evolution
Meaning: the functioning of finding the root of an expression.

Antecedent together with Consequent

Meaning: the get-go together with minute term of a ratio respectively.

• "The ratio a:b is equal to the ratio ma:mb; that is, the value of a ratio remains unaltered if the antecedent together with the consequent are multiplied or divided past times the same quantity".
• "A ratio is said to live on a ratio of greater inequality, of less inequality, or of equality, according every bit the antecedent is greater than, less than, or equal to the consequent. 

[There are loads of interesting price inward the ratio chapter - including commensurable together with subduplicate.]

Transposition
Meaning: The human activity of transferring something to a dissimilar place.

[This hasn't disappeared, but the role of the phrase 'by transposition' or 'transposing' inward worked examples is something nosotros don't run across inward schools anymore].

There are many to a greater extent than words together with phrases inward this majority which seem to guide keep disappeared from the daily mathematical vocabulary of secondary schools - far besides many to listing here. Whence I volition relieve the balance for about other post. I promise you lot observe all this every bit interesting every bit I do. No incertitude mortal volition right away contact me to nation that they role all these words inward their classroom on a regular basis...!