Kategóriák: Minden - variables - change

a Rebeca Bazua 7 éve

244

Increments and Differentials

Differentials and increments are mathematical concepts used to describe changes in quantities. Differentials provide an estimate of the change based on the tangent line of a function, symbolized as dy ≈ Δy and calculated using the derivative f'

Increments and Differentials

Increments and Differentials

Differentials of y (dy)

They give an estimate of the real change on the value of a quantity (or variable).
dy ≈ Δy dy = f ’ (x) * dx
Infinitely small quantities.

Increments vs Differentials

Differentials
The information comes from the tangent line.

dy ≈ Δy dx = Δx dy = f ’(x) * dx dx = x2 – x1 f ’(x) * dx ≈ y2 – y1

Give an estimate of the real change among two values.
Increments
The information comes from the actual situation (f(x)).

y2 = Δy + y1 x2 = Δx + x1 Δy = y2 – y1 Δx = x2 – x1

Give the real change between two quantities.

Increment (Δy)

Can be positive or negative (decrement).
To calculate an increment you need to obtain the difference between the final and the initial value:
Δy = y2 – y1 Δx = x2 – x1
To denote an increment we use upper case delta: Δ
Used to show a change in the value of a variable.

Δy: change on the variable y

Δt: change in time

ΔT: change in Temperature

Δy: change in the volume of an object

Δp: price

When a changing quantity passes from an initial value to another value, it is said that it had an increment.