Q. For the function f(x)=−x2−5x+9, find the slope of the secant line between x=−2 and x=2.Answer:
Calculate f(−2): To find the slope of the secant line between two points on a function, we use the formula for slope, which is the change in y divided by the change in x, or x2−x1f(x2)−f(x1). We need to calculate the function values at x=−2 and x=2.
Calculate f(2): First, we calculate f(−2). Plugging −2 into the function, we get f(−2)=−(−2)2−5(−2)+9=−4+10+9.
Find slope formula: Simplifying f(−2), we get f(−2)=−4+10+9=15.
Calculate slope: Next, we calculate f(2). Plugging 2 into the function, we get f(2)=−(2)2−5(2)+9=−4−10+9.
Calculate slope: Next, we calculate f(2). Plugging 2 into the function, we get f(2)=−(2)2−5(2)+9=−4−10+9. Simplifying f(2), we get f(2)=−4−10+9=−5.
Calculate slope: Next, we calculate f(2). Plugging 2 into the function, we get f(2)=−(2)2−5(2)+9=−4−10+9. Simplifying f(2), we get f(2)=−4−10+9=−5. Now we have the two points (−2,f(−2)) and (2,f(2)), which are (−2,15) and (2,−5). We can use these to find the slope of the secant line: slope=2−(−2)f(2)−f(−2).
Calculate slope: Next, we calculate f(2). Plugging 2 into the function, we get f(2)=−(2)2−5(2)+9=−4−10+9. Simplifying f(2), we get f(2)=−4−10+9=−5. Now we have the two points (−2,f(−2)) and (2,f(2)), which are (−2,15) and (2,−5). We can use these to find the slope of the secant line: slope=2−(−2)f(2)−f(−2). Plugging in the values, we get 20.
Calculate slope: Next, we calculate f(2). Plugging 2 into the function, we get f(2)=−(2)2−5(2)+9=−4−10+9. Simplifying f(2), we get f(2)=−4−10+9=−5. Now we have the two points (−2,f(−2)) and (2,f(2)), which are (−2,15) and (2,−5). We can use these to find the slope of the secant line: slope=2−(−2)f(2)−f(−2). Plugging in the values, we get 20. Simplifying the slope, we get 21.
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