Question

If y= x^2+3x+5, evaluate y given x= 2+i .

Answer 1

Replace x with 2+i and solve
Remember that i is the square root of -1
My phone automatically capitalizes I, so don’t be confused by that!
y=(2+I)^2 + 3(2+I) +5
y=4+4i-1+6+3i+5
y=7i+14