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Find the equation of the tangent to the curve (y = frac{x – 1}{2x +…

Find the equation of the tangent to the curve (y = frac{x – 1}{2x + 1}, x neq -frac{1}{2}) at the point (1, 0).

Explanation

(y = frac{x – 1}{2x + 1}, x neq -frac{1}{2})

Using the quotient rule, we have 

(frac{mathrm d y}{mathrm d x} = frac{(2x + 1). 1 – (x – 1). 2}{(2x – 1)^{2}})

= (frac{2x + 1 – 2x + 2}{(2x + 1)^{2}})

(frac{mathrm d y}{mathrm d x} = frac{3}{(2x + 1)^{2}})

At (1, 0), (frac{mathrm d y}{mathrm d x} = frac{3}{(2(1) + 1)^{2}} = frac{3}{9} = frac{1}{3})

Equation : (frac{y – 0}{x – 1} = frac{1}{3})

(y = frac{1}{3}(x – 1))