Question

dada a função f(x)=x/2-2/x, calcule o valor de f (2/5) - f (-1/10)

Answer 1

f(x)=x/2-2/x
f (2/5)= (2/5)/2 - 2/(2/5)
f(2/5)= 2/5*1/2 - 2*5/2
f(2/5)= 1/5 - 5
f(2/5)= -24/5

f (-1/10)= (-1/10)/2 - 2/(-1/10)
f(-1/10)= -1/10*1/2 - 2*-10
f(-1/10)= -1/20 +20
f(-1/10)= 399/20

f(2/5)-f(-1/10)= -24/5 -399/20
f(2/5)-f(-1/10)= -96/20 -399/20
f(2/5)-f(-1/10)= -495/20
f(2/5)-f(-1/10)= -99/4