PLEASE ANSWER IT I NEED HELP NOW THANK YOU SO SO MUCH.

Step-by-step explanation:

a  is just the peak value which looks like  a = 2.5

this cos wave function has a phase shift of 60°    A normal cos function with no phase shift has a b of zero

so to make this cos function to have NO phase shift we would substract 60° then cos 0 would be 1×a  so b = -60°

y = 2.5cos(x-60)     when x =60    cos(60-60) = 1     y = 2.5×1

The second question is odd but i'll try

   y = f(2x)      (4, 10)       the origianl f(x) was (4, 5)

   y = f(x) - 7    (4, -2)

step-by-step explanation:

if you want to solve percent error follow these steps.

1. subtract the accepted value from the experimental value.

2. take the absolute value of step 1.

3. divide that answer by the accepted value.

4. multiply that answer by 100 and add the % symbol to express the answer as a percentage.

if you want to solve percent of change just do this.

1. work out the difference (increase) between the two numbers you are comparing.

2. divide the increase by the original number and multiply the answer by 100. if your answer is a negative number then this is a percentage decrease.

hope this : )