# ! You can't use \eqno' in math mode

what is wrong with this??? please,can anyone help?

$$\label{probabilityy} P^{t}({E_{0})=P_{0}+(1-P_{0})P_{1}+ (1-P_{0})(1-P_{1})P_{2}+.......+P_{n}\Pi_{k_{0}}^{n-1}(1-P_{k})$$

• This question appears to be off-topic because it's really not applicable to a wider audience (due to a typo). – Werner Jun 3 '14 at 14:31
• Au contraire – this is actually quite a useful question, because the error message is regrettably such a useless one: ‘of course I can use \eqno in a maths mode – that's the point!’ that it distracts from the real problem. You can't use \eqno in an inner maths mode, and that's what TeX's objecting to. Ie, this is a silly brace matching error, but I didn't realise the problem when I hit it, until I found this question (doh!). The similar questions elsewhere on the site are less useful, because they distract with too many other errors. Sooooo, yet another 10 points for David. – Norman Gray Jan 5 '15 at 18:38
• @NormanGray thanks:-) you can vote for re-open – David Carlisle Jan 6 '15 at 1:18

You have a spurious extra {
P^{t}({E_{
`