Question

( y=frac{x^{2}+3 x-4}{x^{2}+7 x+12}, x in R )
( y=x^{2}+4 x-x-4 )
( x^{2}+3 x+4 x+12 )
( y=(x+4)(x-1) )
( (x+3)(x+4) )
( x eq-3,-4 ) as denominater
cannot be 0
ans ( x in(-infty,-3) cup(-3,-4) cup(-4, infty) )

# Q.2 .: x² +38-4 Ifx is real then find the range of y=- x? +7x +12

Solution