x0=2.5 .
x 1=(2.5+5/2.5)/2=2.25。
x2 =(2.25+5/2.25)/2 = 2.236 1 1 1 .
√5 is an irrational number, and there are two commonly used calculation methods: series method and Taylor expansion method of √( 1+x). If n is large enough, enough accuracy can be achieved. Take the first four items for calculation, namely: √5≈2.236.
Root/root symbol ()
This is a mathematical symbol. The root sign is a symbol used to represent the root operation of a number or an algebra. If a? =b, then A is the n-th square root of B or A is the 1/n power of B, and the n-th handwriting and printing are represented by n √. The number of roots or algebraic expressions are written in the area surrounded by the left √ and right √ of the symbol and the lower part of a horizontal part above the symbol, and cannot be out of bounds.