The function f is defined by f(x)=x2−5−5cos(3x). Use a calculator to write the equation of the line tangent to the graph of f when x=−1. You should round all decimals to 3 places.Answer:
Q. The function f is defined by f(x)=x2−5−5cos(3x). Use a calculator to write the equation of the line tangent to the graph of f when x=−1. You should round all decimals to 3 places.Answer:
Calculate Derivative of f: To find the equation of the tangent line to the graph of f at x=−1, we need to calculate the derivative of f, which will give us the slope of the tangent line at that point.The derivative of f with respect to x, f′(x), is given by:f′(x)=dxd[x2−5−5cos(3x)]Using the power rule and the chain rule, we find:f′(x)=2x−0−5⋅(−sin(3x))⋅3f′(x)=2x+15sin(3x)Now we need to evaluate this derivative at x=−1.f′(−1)=2(−1)+15sin(3(−1))f′(−1)=−2+15sin(−3)Using a calculator, we find sin(−3) and round to three decimal places.
Evaluate Derivative at x=−1: Using a calculator, sin(−3)≈−0.141. Now we plug this value into the derivative to find the slope of the tangent line at x=−1. f′(−1)=−2+15(−0.141) f′(−1)=−2−15×−0.141 f′(−1)=−2+2.115 f′(−1)≈0.115 This is the slope of the tangent line at x=−1.
Find y-coordinate at x=−1: Next, we need to find the y-coordinate of the point on the graph of f at x=−1 to determine the point of tangency. We do this by evaluating f(−1). f(−1)=(−1)2−5−5cos(3(−1)) f(−1)=1−5−5cos(−3) Using a calculator, we find cos(−3) and round to three decimal places.
Determine Point of Tangency: Using a calculator, cos(−3)≈0.990. Now we plug this value into the function to find the y-coordinate.f(−1)=1−5−5(0.990)f(−1)=1−5−4.950f(−1)=−4−4.950f(−1)≈−8.950The point of tangency is (−1,−8.950).
Use Point-Slope Form: Now we have the slope of the tangent line, m=0.115, and a point on the line, (−1,−8.950). We can use the point-slope form of the equation of a line to find the equation of the tangent line:y−y1=m(x−x1)y−(−8.950)=0.115(x−(−1))y+8.950=0.115(x+1)Now we simplify the equation.
Simplify the Equation: Simplifying the equation, we get:y+8.950=0.115x+0.115y=0.115x+0.115−8.950y=0.115x−8.835This is the equation of the tangent line to the graph of f at x=−1, rounded to three decimal places.
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