Graphs of Sine and Cosine · Challenge problem

$y=4\cos\!\big(\tfrac{\pi}{4}(x-2)\big)+6$

$y=4\cos\!\big(\tfrac{4}{\pi}(x-2)\big)+5$

$y=4\cos\!\big(\tfrac{\pi}{4}(x-2)\big)-5$

$y=4\cos\!\big(\tfrac{\pi}{4}(x-2)\big)+5$