Question

$\text{sin}\dfrac{\mathit{\pi x}}{4}=1$

Answer 1

πx/4= π/2 + 2πk, k∈Z
x = (π/2) * (4/π) + (2πk) * (4/π) 
x = 2 + 8k, k∈Z

Answer 2

$sin \frac{ \pi x}{4} =1\\\\ \frac{ \pi x}{4}= \frac{ \pi }{2} +2 \pi n\\\\x=2+8n$