Question

Find the square root of -15-81​

Answer 1

Step-by-step explanation:

let y = sqrt(1581)

y = sqrt(1600-19)

let x=1600, del(x)=19

y = sqrt(x), differentiation w.r.t. x

dy/dx = 1/sqrt(x) × 1/2

because del(y) = dy/dx × del(x)

put these values,

del(y) = 1/sqrt(1600)×1/2×19

del(y) = 1/40×1/2×19

del(y) = 0.2375

sqrt((x) - del(x) ) = y-del(y)

sqrt(1600-19) = sqrt(x)-0.2375

sqrt(1581) = sqrt(1600)-0.2375

sqrt(1581) = 40-0.2375

sqrt(1581) = 39.7625