Question

if y-1/y=4 so y^2+1/y^2 value must be ​

Answer 1

Step-by-step explanation:

y+y1=9

Squaring both side

(y+y1)2=92

y2+y21+2×y×y1=81

y2+y21=81−2=79

Squaring

(y2+y21)2=(79)2

y4+y41+2×y2×y21=6241

y4+y41=6,239.