Y = g (x + at) + F (X-AT), it is proved that the second derivative of Y for t is equal to a ^ 2 times of the second derivative of Y for X
y=g(x+at)+f(x-at)
ay/at=ag' -af'
a^2y/at^2=a^2g"+a^2f"
ay/ax=g' +f'
a^2y/at^2=g"+f"
RELATED INFORMATIONS
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- 13. The function f (x) = AX3 + 3x2 + 2, if f '(- 1) = 4, then the value of a is equal to______ .
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