We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.

Below is the graph of y = acos(bx+c)+d, where a, b, and c are positive, and c is as small as possible. Find a + b + c+d.

 Oct 28, 2019

The graph of cos is shifted up (by d)   , shifted RIGHT (to make c as small as possible ----- c will be NEGATIVE) and amplified (by a)  and period is increased to 3pi (from normal 2pi)


Amplification   'a'    Normal cosine is from -1 to 1  ( amplitude = 1)   this graph is from -1 to 3  (amplitude = 2)    so  a = 2


Period is changed by b    = 2/3

shifted LEFT by 3pi/2 (to make c as small as possible, but still positive) but multiplied by 2/3 (above) makes it just pi   pi = c

And finally ....shifted UP  from midline = 0 to midline = 1       1 = d



Here is a graph:




( RED text is edited/corrected text....THANX to CPhil !)

 Oct 28, 2019
edited by ElectricPavlov  Oct 28, 2019
edited by ElectricPavlov  Oct 29, 2019

18 Online Users