The value of {}^7P_3 - 3({}^6P_2) is equal to | vedclass

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(C) We have,${}^7P_3 - 3({}^6P_2)$ $= \frac{7!}{(7-3)!} - 3 	imes \frac{6!}{(6-2)!}$ $= \frac{7!}{4!} - 3 	imes \frac{6!}{4!}$ $= \frac{7 	imes 6!}

Vedclass · Accepted Answer

${}^6P_3$

Vedclass · Answer

(C) We have,${}^7P_3 - 3({}^6P_2)$ $= \frac{7!}{(7-3)!} - 3 	imes \frac{6!}{(6-2)!}$ $= \frac{7!}{4!} - 3 	imes \frac{6!}{4!}$ $= \frac{7 	imes 6!}{4!} - \frac{3 	imes 6!}{4!}$ $= \frac{6!}{4!} (7 - 3)$ $= \frac{6!}{4!} 	imes 4$ $= \frac{6 	imes 5 	imes 4!}{4!} 	imes 4$ $= 30 	imes 4 = 120$ Alternatively,using the definition of permutation: ${}^6P_3 = \frac{6!}{(6-3)!} = \frac{6!}{3!} = 6 	imes 5 	imes 4 = 120$ Thus,the value is equal to ${}^6P_3$.

The value of ${}^7P_3 - 3({}^6P_2)$ is equal to

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