derivative of y= 1/(sqrt(a^2-x^2))
We save the definition: y = 1a2 -x2
The expression 1a2 -x2 contains several variables: the variable x is chosen for derivation
To simplify differentiation, we rewrite 1a2 -x2 as (a2 -x2)-12
Let's perform the differentiation: ddx((a2 -x2)-12)
We differentiate using: ddx(fn) = n·ddx(f)·fn -1 (where f = a2 -x2)
ⓘ The derivative of x^n is n*x^(n-1): ddx((a2 -x2)-12) = -12·ddx(a2 -x2)·(a2 -x2)-32
-12·ddx(a2 -x2)·(a2 -x2)-32
ⓘ Multiplying a fraction by a term multiplies its numerator: -12·ddx(a2 -x2)·(a2 -x2)-32 = -1·ddx(a2 -x2)·(a2 -x2)-322 = -ddx(a2 -x2)·(a2 -x2)-322■The factor is moved to the numerator or the denominator by changing the sign of its exponent, for a nonzero base: -ddx(a2 -x2)·(a2 -x2)-322 = -ddx(a2 -x2)2·(a2 -x2)32
-ddx(a2 -x2)2·(a2 -x2)32
ⓘ The derivative of a sum is the sum of the derivatives: ddx(a2 -x2) = ddx(a2) + ddx(-x2)
-ddx(a2) + ddx(-x2)2·(a2 -x2)32
ⓘ The derivative of a constant is zero: ddx(a2) = 0■The derivative of x^n is n*x^(n-1): ddx(-x2) = -2x
-0 -2x2·(a2 -x2)32
ⓘ Adding 0 changes nothing: 0 -2x = -2x■Two minus signs cancel out: -(-2x2·(a2 -x2)32) = 2x2·(a2 -x2)32
2x2·(a2 -x2)32
ⓘ A fraction is simplified by dividing the numerator and the denominator by the same number: 2x2·(a2 -x2)32 = x(a2 -x2)32
▶Derivative:   x(a2 -x2)32