Question

For what value of k is the polynomial 2y³+9y²+y+k is divided by x-1 ?

Answer 1

put x=1 in the polynomial because it's a root of it .now 2(1)^3+9(1)^2+1+k=0
k=-12

Answer 2

ᴘᴜᴛ x=1 ɪɴ ᴛʜᴇ ᴘᴏʟʏɴᴏᴍɪᴀʟ ʙᴇᴄᴀᴜsᴇ ɪᴛ's ᴀ ʀᴏᴏᴛ ᴏғ ɪᴛ .ɴᴏᴡ 2(1)^3+9(1)^2+1+ᴋ=0
ᴋ=-12