这道数学题有点难

https://na.imoemh.com/images/p/bf/c8/e281bd15751193abcf1f25ca9bc1.jpg,https://na.imoemh.com/images/p/50/a8/fd60c6b9cce01e88b0f9fea2c3ca.jpg,https://na.imoemh.com/images/p/58/f4/dea29696b067a9268db8c079ee14.jpg,https://na.imoemh.com/images/p/4b/2c/7e7127393248e4f40f23b0769faf.jpg,https://na.imoemh.com/images/p/19/c5/e31e502b963194bdf6cc2ab0c606.jpg,https://na.imoemh.com/images/p/e5/50/42f2d526f5f128dd69c4a5817b52.jpg