What value does 25\sqrt{25}25 denote, even though both 5 and -5 solve x2=25x^2=25x2=25?
A
999
B
25=\strong5\sqrt{25}=\strong{5}25=\strong5, the positive square root.
C
The symbol a\sqrt{a}a denotes the positive square root of aaa. Keeping an irrational root as a surd gives an exact value.
D
x=2x=2x=2
1.5.2 Surds Flashcards
Flashcards for AQA A Level Maths 1.5.2 Surds, covering the key formulae, methods and definitions you need to recall for Paper 1, Paper 2 and Paper 3. 21 cards, matched to the AQA A Level Maths (7357) specification. Recall questions account for roughly 50% of marks at A Level Maths, so these target the marks you can secure before the paper starts.