If `cotA+cotB+cotC``=``k(1/x^2+1/y^2+1/z^2)` then the value of `k` is
`(A)` `R^2`
`(B)` `2R`
`(C)` `/_\`
`(D)`a^2+b^2+c^2`

If 1/(1+2x+x^2)= 1+a_1x+a_2x^2+….. then the value of a_r is (A) 2 (B) r+1 (C) r (D) 2r

If (bx)/c+(cy)/a+(az)/b=((a^2+b^2+c^2)/k) then the value of k is (A) R (B) S (C) 2R (D) 3/2R

In triangle A B C , if cotA *cotC=1/2a n dcot B* cotC=1/(18), then the value of tanC is

In triangle ABC, if cotA⋅cotC= 1 / 2 and cotB⋅cotC= 1 / 18 , then the value of tanC is

If the lines (x-1)/2=(y+1)/3=(z-1)/4 and (x-3)/1=(y-k)/2=z/1 intersect then the value of k is (A) 3/2 (B) 9/2 (C) -2/9 (D) -3/2

If x^(140)+2x^(151)+k is divisible by x+1 , then the value of k is=? (a) 1 (b) -3 (c) 2 (d) -2

If the system of equations, x+2y-3z=1,(k+3)z=3,(2k+1)x+z=0 is inconsistent, then the value of k is (A) -3 (B) 1/2 (C) 0 (D) 2

In A B C , if b^2+c^2=2a^2, then value of (cotA)/(cotB+cotC) is 1/2 (b) 3/2 (c) 5/2 (d) 5/2

If a , b , c are consecutive positive integers and (log(1+a c)=2K , then the value of K is (a) logb (b) loga (c) 2 (d) 1

For (i) A + B ⇋ C K_c = K_1 (ii) 2C⇋D K_c=K_2 Then the value of K_c for 2D + A + B ⇋ 5C will be