Question
Number of real solution of 5- _2|x| =3- _2|x| is equal to
Number of real solution of 5- _2|x| =3- _2|x| is equal to
B. 2
aligned & Let & _2|x| & =t (i)\\ & & 5-t & =3-t \\ & & 5-t & =(3-t)^2 \\ & & 5-t & =9+t^2-6 t aligned aligned & t^2-5 t+4=0 \\ & (t-4)(t-1)=0 \\ & t=1 or 4 [rejected] \\ & [ 5-4 =3-4,1 -1] \\ & _2|x|=1 \\ & |x|=2 \\ & x= 2 aligned Total 2 real solutions.
Related: Mathematics — Functions · All PYQ Banks