Q: If the input number is a, the output number is _ √ A- 1. _ _ _ _ _ _.
2。 It is known that m power of 16 = 2N-2 power of 2 multiplied by 4; N power of 27 = M+3 power of 3 times 9. Find the values of m and n (detailed process)
Answer: According to the meaning of the question, you must:
16^m=2^(2n-2)*4……( 1)
27^N=3^(M+3)*9 ……(2)
From (1):
2^4M=2^2N
4M=2N
m = 1/2 * N……………………(3)
From (2):
3^3N=3^(M+5)
3N=M+5 …………(4)
Substituting (3) into (4) gives: N=2,
Substitute N=2 into (3): M= 1.
3。 The sales of a commercial building this year 1 month is 6.5438+0 million yuan. In February, due to various reasons of poor management, sales fell by 4%. Later, the management was improved, and the sales in April reached 6.5438+0.5 million yuan. Find the average monthly growth rate for three or four months. Accurate to 0. 1% (detailed process)
Solution: Let the average monthly growth rate of three or four months be x, then:
100*( 1-4%)( 1+x)^2= 150
96( 1+x)^2= 150
( 1+x)^2= 1.5625
1+x= 1.25
X 1=25% x2=-2.25 (omitted)
That is, the average monthly growth rate in March and April is 25%.