If `6P_r: 6P_5=1 :2 ,` then prove that `r=4`

If .^(6)P_(r): .^(6)P_(5) = 1:2 , find the value of r.

If .^(6)P_(r): .^(6)P_(5) = 1:2 , find the value of r.

In Fig. 6.15, /_P Q R=/_P R Q , then prove that /_P Q S=/_P R T .

In Fig. 6.15, /_P Q R=/_P R Q , then prove that /_P Q S=/_P R T .

If ^28p_r=6^28C_r , prove that r = 3

If p,q and r are in AP,then prove that (p+2q-r)(2q+r-p)(r+p-q)=4pqr

In Fig. 6.44, the side QR of PQR is produced to a point S. If the bisectors of /_P Q R and /_P R S meet at point T, then prove that /_Q T R=1/2/_Q P R .

If "^(5)P_r = 2^(6)P_(r - 1) then find thevalue of r.

If ^9p_5+5^9p_4=^10p_r .prove that r=5