Search any question & find its solution
Question:
Answered & Verified by Expert
${ }^{15} P_8=A+8 \cdot{ }^{14} P_7 \Rightarrow A=$
Options:
Solution:
2144 Upvotes
Verified Answer
The correct answer is:
${ }^{14} P_8$
$\begin{aligned} & \text { Given, }{ }^{15} P_8=A+8 \cdot{ }^{14} P_7 \\ & \Rightarrow \quad \frac{15 !}{7 !}=A+8 \cdot \frac{14 !}{7 !} \\ & \Rightarrow \quad A=\frac{14 !}{7 !}(15-8)=\frac{14 !}{7 !}(7) \\ & =\frac{14 !}{6 !}={ }^{14} P_8 \\ & \end{aligned}$
Looking for more such questions to practice?
Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.