a. 134^2 - 68.134 + 34^2 = ( 134 - 34 ) ^2 = 100^2 = 10000
b. 9^8.2^8 - ( 18^4 - 1 )(18^4 + 1 ) = 18^8 - 18^8 + 1 = 1
c. 100^2 - 99^2 + 98^2 - 97^2 + ... + 2^2 - 1
=( 100 - 99 )( 100 + 99 ) + ( 98 - 97 )( 98 + 97 ) + ... + ( 2 - 1 )( 2 + 1 )
= 100 + 99 + 98 + 97 + ... + 2 + 1
=( 100 + 1 ).100:2 = 5050
\(I\)Tính nhanh
\(a.127^2+146.127+73^2\)
\(b.9^8.2^8\left(18^4-1\right)\left(18^4+1\right)\)
\(c.100^2-99^2+98^2-97^2+...+2^2-1^2\)
\(d.\frac{780^2-220^2}{125^2+150.125+75^2}\)
\(II.\)Rút gọn các biểu thức
\(x^2\left(x+4\right)\left(x-4\right)-\left(x^2+1\right)\left(x^2-1\right)\)
\(\left(y-3\right)\left(y+3\right)\left(y^2+9\right)-\left(y^2+2\right)\left(y^2-2\right)\)
\(5\left(2x-1\right)^2+4\left(x-1\right)\left(x+3\right)-2\left(5-3x\right)^2\)
Tính nhanh
a,\(A=100^2-99^2+98^2-97^2+...+2^2-1^2\)
b,\(B=\left(20^2+18^2+...+2^2\right)-\left(19^2+17^2+....+3^2+1^2\right)\)
c,\(C=\frac{780^2-220^2}{125^2+150.125+75^2}\)
d,\(D=2.\left(a+5\right).\left(a+4\right)-\left(a+5\right)^2-\left(a^2-9a-17\right)\)với a=99
Tính nhanh:
a) \(100^2-99^2+98^2-97^2+...+2^2-1^2\)
b) \(\left(20^2+18^2+16^2+...+4^2+2^2\right)-\left(19^2+17^2+...+3^2+1^2\right)\)
Tính nhanh:
a) \(100^2-99^2+98^2-97^2+...+2^2-1^2\)
b) \(\left(20^2+18^2+16^2+...+4^2+2^2\right)-\left(19^2+17^2+...+3^2+1^2\right)\)
Tính:
a) \(T=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^{16}+1\right).\)
b)\(U=100^2-99^2+98^2-97^2+...+4^2-3^2-1^2\)
Bài 11.Tính giá trị biểu thức
1) \(A=127+146.127+73^2\)
2) \(B=98.28-\left(18^4-1\right).\left(18^4+1\right)\)
3) \(C=-1^2+2^2-3^2+4^2+.....-99^2+100^2\)
4) \(D=\left(3+1\right).\left(3^2+1\right).\left(3^4+1\right).\left(3^8+1\right).\left(3^{16}+1\right)\)
5) \(E=1^2-2^2+3^2-4^2+.....-2004^2+2005^2\)
Rút gọn biểu thức:
a) \(\left(x^2-2x+2\right)\left(x^2-2\right)\left(x^2+2x+2\right)\left(x^2+2\right)\)
b) \(\left(a+b+c\right)^2+\left(a+b-c\right)^2+\left(2a-b\right)^2\)
c) \(100^2-99^2+98^2-97^2+...+2^2-1^2\)
d) \(3\left(2^2+1\right)\left(2^4+1\right)...\left(2^{64}+1\right)+1\)
Giup mình nha
Rút gọn biểu thức:
a) \(\left(x^2-2x+2\right)\left(x^2-2\right)\left(x^2+2x+2\right)\left(x^2+2\right)\)
b) \(\left(a+b+c\right)^2+\left(a+b-c\right)^2+\left(2a-b\right)^2\)
c) \(100^2-99^2+98^2-97^2+...+2^2-1^2\)
d) \(3\left(2^2+1\right)\left(2^4+1\right)...\left(2^{64}+1\right)+1\)
Giup mình vs mình dang cần gấp
Rút gọn biểu thức:
a) \(\left(x^2-2x+2\right)\left(x^2-2\right)\left(x^2+2x+2\right)\left(x^2+2\right)\)
b) \(\left(a+b+c\right)^2+\left(a+b-c\right)^2+\left(2a-b\right)^2\)
c) \(100^2-99^2+98^2-97^2+...+2^2-1^2\)
d) \(3\left(2^2+1\right)\left(2^4+1\right)...\left(2^{64}+1\right)+1\)
Giup mình vs mình dang cần gấp
