If the value of c prescribed in Rolle’s theorem for the function f(x) = 2x (x – 3)n on the interval 
write the value of n (a positive integer).
f(x) = 2x (x – 3)n
Differentiating the above-mentioned function with respect to ‘x’,
f’(x) = 2 [xn (x – 3)n – 1 + (x – 3)n]
-n + 3 = 0
-n = -3
n = 3
Hence, the required value of ‘n’ is 3.
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