A、\(\displaystyle \frac{{a+2}}{{b+2}}=\frac{a}{b}\)
B、\(\displaystyle \frac{{a-2}}{{b-2}}=\frac{a}{b}\)
C、\(\displaystyle \frac{{{{a}^{2}}}}{{{{b}^{2}}}}=\frac{a}{b}\)
D、\(\displaystyle \frac{{\frac{1}{2}a}}{{\frac{1}{2}b}}=\frac{a}{b}\)
因为a≠b,所以\(\displaystyle \frac{{a+2}}{{b+2}}≠\frac{a}{b}\),所以A错误;\(\displaystyle \frac{{a-2}}{{b-2}}≠\frac{a}{b}\),选项B错误;\(\displaystyle \frac{{{{a}^{2}}}}{{{{b}^{2}}}}≠\frac{a}{b}\),所以选项C错误;选项D正确。
