设实对称矩阵<img class="jc-formula" data-tex="A" src="https://huaweicloudobs.ahjxjy.cn/53F870B8D448BB3DB08A67264B6329F9.png" style="vertical-align: middle;"/>与<img class="jc-formula" data-tex="B=\left( 1\\ \quad -1\quad \quad \\ \quad \quad \quad \quad 2 \right) " src="https://huaweicloudobs.ahjxjy.cn/F83DB5DDA8A8CECCC73531E5092F8FAA.png" style="vertical-align: middle;"/>相似,则<img class="jc-formula" data-tex="R(A)=" src="https://huaweicloudobs.ahjxjy.cn/EA3EEAC4F5D815FE2E7F3ED1B8EDC350.png" style="vertical-align: middle;"/>[填空1].