P.据/span>(据/span>X据/span>)据/span>还是据/p>
让据span class="katex">
F据/span>(据/span>X据/span>)据/span>=据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>。然后据span class="katex-display">
F据/span>(据/span>1据/span>)据/span>=据/span>(据/span>-据/span>1据/span>)据/span>(据/span>-据/span>2据/span>)据/span>(据/span>-据/span>3.据/span>)据/span>=据/span>-据/span>6.据/span>, 所以据/span>P.据/span>1据/span>(据/span>X据/span>)据/span>=据/span>-据/span>6.据/span>1据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>。据/span>
让据span class="katex">
F据/span>(据/span>X据/span>)据/span>=据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>。然后据span class="katex-display">
F据/span>(据/span>2据/span>)据/span>=据/span>(据/span>1据/span>)据/span>(据/span>-据/span>1据/span>)据/span>(据/span>-据/span>2据/span>)据/span>=据/span>2据/span>, 所以据/span>P.据/span>2据/span>(据/span>X据/span>)据/span>=据/span>2据/span>1据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>。据/span>
让据span class="katex">
F据/span>(据/span>X据/span>)据/span>=据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>。然后据span class="katex-display">
F据/span>(据/span>3.据/span>)据/span>=据/span>(据/span>2据/span>)据/span>(据/span>1据/span>)据/span>(据/span>-据/span>1据/span>)据/span>=据/span>-据/span>2据/span>, 所以据/span>P.据/span>3.据/span>(据/span>X据/span>)据/span>=据/span>-据/span>2据/span>1据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>。据/span>
让据span class="katex">
F据/span>(据/span>X据/span>)据/span>=据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>。然后据span class="katex-display">
F据/span>(据/span>4.据/span>)据/span>=据/span>(据/span>3.据/span>)据/span>(据/span>2据/span>)据/span>(据/span>1据/span>)据/span>=据/span>6.据/span>, 所以据/span>P.据/span>4.据/span>(据/span>X据/span>)据/span>=据/span>6.据/span>1据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>。据/span>
因此,据span class="katex-display">
P.据/span>(据/span>X据/span>)据/span>=据/span>1据/span>×据/span>(据/span>-据/span>6.据/span>1据/span>)据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>+据/span>4.据/span>×据/span>2据/span>1据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>+据/span>1据/span>×据/span>(据/span>-据/span>2据/span>1据/span>)据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>4.据/span>)据/span>+据/span>5.据/span>×据/span>6.据/span>1据/span>(据/span>X据/span>-据/span>1据/span>)据/span>(据/span>X据/span>-据/span>2据/span>)据/span>(据/span>X据/span>-据/span>3.据/span>)据/span>。据/span>
简化使据span class="katex">
P.据/span>(据/span>X据/span>)据/span>=据/span>6.据/span>1据/span>3.据/span>X据/span>3.据/span>-据/span>1据/span>6.据/span>X据/span>2据/span>+据/span>6.据/span>2据/span>1据/span>5.据/span>X据/span>-据/span>2据/span>1据/span>。据/span>
□据/span>