Edexcel A Level Maths

The mark schemes (from current spec past paper questions on that topic from PMT) often say the last accuracy mark is for getting the answers and no wrong answers in the range, so you would lose that last mark. It doesn't clearly say what to do with wrong or correct answers outside the range but you'd be more likely to get away with those (but avoid it when you can ofc). I reccommend when possible using the calculator on both sides of the original equation to check all the answers