Question

if x*y=x+y-x×y find 8*6​

Answer 1

Answer:

Try a technique of Diophantus. It is an easier method for solving problems like this one and it takes less work.

Let x=4+c and y=4−c

where c is number. Then

x+y=4+c+4−c=8.

From this

xy=6 is

(4+c)(4−c)=6.

Find c:

16−c2=6,

−16+c2=−6,

c2=−6+16=10,

c=±10−−√.

Then x=4+(±10−−√)=4±10−−√

and y=4−(±10−−√)=4∓10−−√.

Put them together and get that

(x, y)=(4±10−−√, 4∓10−−√).