Element replacement in a vector

Hi there. I have a row vector like a = [3 4 6 8 9] then I want to replace third element which is 6 with 5 and 8 so the new vector becomes b = [3 4 5 8 8 9]. What is the function to convert the vector. Thanks

Answer 1

[Image Analyst]

Try this:

b = [a(1:2), 5, 8, a(4:end)]