Solve 1/(x-4)*1/(x-3)

$$\frac { 1 } { ( x - 4 ) } \times \frac { 1 } { ( x - 3 ) }$$

Evaluate

$$\frac{1}{\left(x-4\right)\left(x-3\right)}$$

Solution Steps

Multiply \frac{1}{x-4} times \frac{1}{x-3} by multiplying numerator times numerator and denominator times denominator.

$$\frac{1}{\left(x-4\right)\left(x-3\right)}$$

Apply the distributive property by multiplying each term of x-4 by each term of x-3.

$$\frac{1}{x^{2}-3x-4x+12}$$

Combine -3x and -4x to get -7x.

$$\frac{1}{x^{2}-7x+12}$$

Differentiate w.r.t. x

$$\frac{7-2x}{\left(\left(x-4\right)\left(x-3\right)\right)^{2}}$$

Steps Using Chain Rule

Multiply \frac{1}{x-4} times \frac{1}{x-3} by multiplying numerator times numerator and denominator times denominator.

$$\frac{\mathrm{d}}{\mathrm{d}x}(\frac{1}{\left(x-4\right)\left(x-3\right)})$$

Apply the distributive property by multiplying each term of x-4 by each term of x-3.

$$\frac{\mathrm{d}}{\mathrm{d}x}(\frac{1}{x^{2}-3x-4x+12})$$

Combine -3x and -4x to get -7x.

$$\frac{\mathrm{d}}{\mathrm{d}x}(\frac{1}{x^{2}-7x+12})$$

If F is the composition of two differentiable functions f\left(u\right) and u=g\left(x\right), that is, if F\left(x\right)=f\left(g\left(x\right)\right), then the derivative of F is the derivative of f with respect to u times the derivative of g with respect to x, that is, \frac{\mathrm{d}}{\mathrm{d}x}(F)\left(x\right)=\frac{\mathrm{d}}{\mathrm{d}x}(f)\left(g\left(x\right)\right)\frac{\mathrm{d}}{\mathrm{d}x}(g)\left(x\right).

$$-\left(x^{2}-7x^{1}+12\right)^{-1-1}\frac{\mathrm{d}}{\mathrm{d}x}(x^{2}-7x^{1}+12)$$

The derivative of a polynomial is the sum of the derivatives of its terms. The derivative of a constant term is 0. The derivative of ax^{n} is nax^{n-1}.

$$-\left(x^{2}-7x^{1}+12\right)^{-2}\left(2x^{2-1}-7x^{1-1}\right)$$

Simplify.

$$\left(x^{2}-7x^{1}+12\right)^{-2}\left(-2x^{1}+7x^{0}\right)$$

For any term t, t^{1}=t.

$$\left(x^{2}-7x+12\right)^{-2}\left(-2x+7x^{0}\right)$$

For any term t except 0, t^{0}=1.

$$\left(x^{2}-7x+12\right)^{-2}\left(-2x+7\times 1\right)$$

For any term t, t\times 1=t and 1t=t.

$$\left(x^{2}-7x+12\right)^{-2}\left(-2x+7\right)$$