write down and simplify the expression of (1-p)^5 .Use this result to find the expansion of (1-x-x^2)^5 in ascending powers of x as far as the terms in x^3 . Find the value of x which would enable you to estimate (0.9899)^5 from this expansion
I'll expand the first part for you and give guidance on the others but I'm not doing your work for you in full.
Any further terms will have multiplication by 0 so there are no more terms. I'll leave simplifying that to you.
What the next question is asking is to substitute for p in the above expansion. You can either do this as above or substitute , if you use the latter remember that the whole expression is squared.
For the third part it is asking you to solve and where q is a constant.