hello
1*2(7)+ 1*2(6)+ 1*2(5)+ 1*2(4) = 240。 This formula seems complicated, but as long as you remember that the 7th power of 2 is 128, the 6th power is 64, the 5th power is 32, and the 4th power is 16, you can easily calculate the result.
Super simple
2 to the 7th power is 128, 6 to 64, 5 to 32, and 4 to 16. These figures add up to 240. The following coefficients are all 0, so don't consider them!
skill
Arrange these coefficients from left to right, and the answer is in front of you! In addition, divided by 2, the answers are arranged from bottom to top.