nasidah
contestada

If y = sin (ax + b), where a & b are constants, which of these is true
(a) d²y/dx² + a²y = 0
(b)d²y/dx² + 2a²y = 0
(c) d²y/dx² - 2a² y = 0
(d) d²y/dx²+ y = 0
(e) d²y/dx² -a²y = 0