Question

Chris wanted to transform the graph of the parent function Y= cot (x) by horizontally compressing it so that it has a period of 2/π units, horizontally Terslating it π/4 units to the right, and vertically translating it 1 unit up. To do so, he graphed the function y= cot (2x-π/4)+1 as shown. What did he do wrong?​

Answer 1

Chris made a mistake by multiplying the x variable by 2 instead of π/2 for the horizontal compression and by not correctly adjusting the phase shift for the horizontal translation. The correct transformed function to meet the desired criteria should be y = cot((π/2)x - π/4) + 1.

Step-by-step explanation:

Chris wanted to alter the graph of the parent function Y = cot(x) to achieve a certain transformation: a horizontal compression for a new period of 2/π units, a horizontal translation of π/4 units to the right, and a vertical translation of 1 unit up. He graphed the function y = cot(2x - π/4) + 1. However, there was a mistake in his transformation.

The correct transformation for a horizontal compression to adjust the period to 2/π units would be by multiplying the x variable by π/2. However, Chris multiplied by 2, which would give the transformed function a period of π units, not 2/π units as intended. Moreover, for a horizontal translation of π/4 units to the right, the correct function would include (x - π/4) inside the cotangent function, not (2x - π/4) as Chris graphed . The correct transformation of the parent function thus should have been y = cot((π/2)x - π/4) + 1 .

Answer 2

The answer is C: He graphed the function y=cot(2x-pi/4)+1 correctly but it was not the right function to graph. He should have graphed y=cot(2x-pi/2)+1.

Step-by-step explanation:

The reason why it is C is because we want a period of pi/2, which would mean that b must be equal to 2 (if you use the period equation for tan and cot, pi/b, in order for pi/b to be equal to pi/2, b must be 2). The form for a trigonometric function is: y = acotb(x-h)+k. And if you notice, the equation he uses has the b already distributed inside the parenthesis, which means that both x and h were already multiplied. If we divide 2x and pi/4 by two, we get x, but h becomes pi/8, which is not equal to pi/4 as required by the problem. The correct equation would be: y = cot(2x-pi/2)+1 because when you divide out the two from inside the parenthesis, you get: y = cot2(x-pi/4)+1, which is the equation that he should've graphed.

I hope this helped you out!

If you have any further questions don't be afraid to ask.