Answer:
The equation of the line tangent to the graph of f at x = -1 is [tex]y = 7\cdot x +13[/tex].
Step-by-step explanation:
From Analytical Geometry we know that the tangent line is a first order polynomial, whose form is defined by:
[tex]y = m\cdot x + b[/tex] (1)
Where:
[tex]x[/tex] - Independent variable, dimensionless.
[tex]y[/tex] - Dependent variable, dimensionless.
[tex]m[/tex] - Slope, dimensionless.
[tex]b[/tex] - Intercept, dimensionless.
The slope of the tangent line at [tex]x = -1[/tex] is:
[tex]f'(x) = -3\cdot x +4[/tex] (2)
[tex]f'(-1) = -3\cdot (-1) +4[/tex]
[tex]f'(-1) = 7[/tex]
If we know that [tex]m = 7[/tex], [tex]x = -1[/tex] and [tex]y = 6[/tex], then the intercept of the equation of the line is:
[tex]b = y-m\cdot x[/tex]
[tex]b = 6-(7)\cdot (-1)[/tex]
[tex]b = 13[/tex]
The equation of the line tangent to the graph of f at x = -1 is [tex]y = 7\cdot x +13[/tex].
