Cho khối tứ diện ABCD có AB, AC, AD đôi một vuông góc với nhau và . Gọi H, K lần lượt là hình chiếu của A lên BC và BD . Thể tích của khối tứ diện ABHK là:              

Chia sẻ

Một số câu hỏi khác có thể bạn quan tâm.

• Choose a word that has different stress pattern:

  modern            rural                      filthy                  transform

• Choose a word that has different stress pattern:

  century                   develop                     social                      history

• Choose the word that has the underlined part pronounced differently from the rest:

  method                filthy                  within                     twentieth

• Choose the word that has the underlined part pronounced differently from the rest:

  transformed                moved              earned               invented

• Choose the word that has the underlined part pronounced differently from the rest:

  about                   plough                 cough                    shout

• Choose the word that has the underlined part pronounced differently from the rest:

  waste                taste            station               statue

• Choose the word that has the underlined part pronounced differently from the rest:

  bury             carry             heavy                many

• Choose the word that has the underlined part pronounced differently from the rest:

  thank             them              thick                thoughtful

• Choose one sentence that has the same meaning as the root one:

  My uncle used to be a high school teacher.
  
  

• Choose one sentence that has the same meaning as the root one:

  The film was so boring that we left in the interval.