The Sūtras
Every technique includes its Sanskrit name, English meaning, when to use it, and at least one fully worked example.
Main Sūtras
Ekādhikena Pūrveṇa
By one more than the previous one
Squaring numbers ending in 5, and converting fractions like 1/19, 1/29.
Nikhilaṁ Navataścaramaṁ Daśataḥ
All from 9 and the last from 10
Multiplication of numbers near a power of 10 (like 98 × 97).
Ūrdhva-Tiryagbhyām
Vertically and crosswise
General multiplication for any two numbers — the 'Vedic multiplication' people know.
Parāvartya Yojayet
Transpose and adjust
Division by numbers slightly above a power of 10, and solving simple equations.
Śūnyaṁ Sāmyasamuccaye
When the sum is the same, that sum is zero
Solving equations where a particular sum equals zero.
Ānurūpyeṇa Śūnyamanyat
If one is in ratio, the other is zero
Used in solving simultaneous equations when coefficients of one variable are in ratio.
Saṅkalana-Vyavakalanābhyām
By addition and by subtraction
Solving simultaneous equations by adding and subtracting them.
Pūraṇāpūraṇābhyām
By the completion or non-completion
Completing a number to the next round figure (like making 97 into 100).
Calanā-Kalanābhyām
Differences and similarities
Used in calculus (differentiation), and in finding roots of quadratics by discriminant.
Yāvadūnam
Whatever the deficiency
Squaring numbers near a power of 10.
Vyaṣṭisamaṣṭiḥ
Part and Whole
Average / mean methods; factorising via averages.
Śeṣāṇyaṅkena Carameṇa
The remainders by the last digit
Computing recurring decimals of fractions like 1/7.
Sopāntyadvayamantyam
The ultimate and twice the penultimate
Solving certain equation types instantly.
Ekanyūnena Pūrveṇa
By one less than the previous one
Multiplying by a number consisting of all 9s.
Guṇitasamuccayaḥ
The product of the sum of coefficients
Verification of polynomial multiplication.
Guṇakasamuccayaḥ
The factors of the sum is equal to the sum of the factors
Verifying factorisation of polynomials.
Sub-Sūtras
Ānurūpyeṇa
Proportionately
Multiplication using a working base proportional to a power of 10.
Śiṣyate Śeṣasaṁjñaḥ
The remainder remains
Quick divisibility tests using remainders.
Ādyamādyenāntyamantyena
First by the first, last by the last
Factorising quadratics quickly.
Yāvadūnaṁ Tāvadūnam
Lessen by the deficiency
Cubing numbers near a base.
Yāvadūnaṁ Tāvadūnīkṛtya Vargaṁ ca Yojayet
What deficit, lessen by that and set up the square
Squaring near a base, expanded form of Yāvadūnam.
Antyayoḥ Daśake'pi
When the final digits add to 10
Multiplication when last digits sum to 10 and other digits are equal.
Antyayoreva
Only the last terms
Algebraic identity solutions using only end terms.
Lopanasthāpanābhyām
By alternate elimination and retention
Factorising expressions in two variables (HCF of polynomials).
Vilokanam
By mere observation
Solving by inspection.
Guṇitasamuccayaḥ Samuccayaguṇitaḥ
The product of the sum equals the sum of the product
Verification rule (cross-check with Sutra 15).
Dhvajāṅka
On the flag
Division by any number using a 'flag digit'.
Samuccayaguṇitaḥ
The sum of the products
Sum-of-products check for factorisations.
Ekanyūnena
By one less (sub-form)
Variant of Sutra 14 for general all-9 multiplication.