根Last we come to "sorry".This can be so hard to say.(最后我们来谈谈"对不起"。这很难说出口。)可知,很难说出口的是"对不起"。故选D。(2)主旨大意题。根据Remember the magic words Start with"please",then say""thank you".(记住神奇的话语:先说"请",然后说"谢谢"。)Last we come to "...
Determine the values of x for which the expression is undefined. \frac{1}{2x^2 - 50} L=D(D^2+4). Solve the linear DE Ly=2+sin t completely. How to tell which Fourier coefficients will have non zero values? Given u(x, t) = t^3 e...
A paper published in the Proceedings of the National Academy of Sciences found that dogs’ faces are structured for complex expression in a way that wolves’ aren’t. For the study, a team looked at two muscles (the RAOL and LAOM muscles) that work together to wide...
The expression cube root of (x^3 y^4) = x^r y^s where x and y are nonnegative real numbers. Find the values of r and s. Using r (t) = < t, 1, 1 >, show that ||r (t)||' not equal to ||r'(t)||. Which of the following functions can...