\(M=\left(100^2+98^2+...+4^2+2^2\right)-\left(101\cdot99+99\cdot97+...+5\cdot3+3\cdot1\right)\)
\(=\left(100^2-100^2+1\right)+\left(98^2-98^2+1\right)+...+\left(4^2-4^2+1\right)+\left(2^2-2^2+1\right)\)
=1+1+...+1
=50
Tính:
a) \(T=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^{16}+1\right).\)
b)\(U=100^2-99^2+98^2-97^2+...+4^2-3^2-1^2\)
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
\(I\)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. \(134^2-68.134+34^2\)
b. \(9^8.2^8-\left(18^4-1\right)\left(18^4+1\right)\)
c. \(100^2-99^2+98^2-97^2+...+2^2-1\)
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 nhanh \(\left(100^2+90^2+...+2^2\right)-\left(1^2+3^2+...+99^2\right)\)
\(\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)...\left(2^{34}+1\right)\) Giúp mình với !!!!
tính nhanh:
a, \(100^2-99^2+98^2-97^2+...+2^2-1^2\);
b,\(\left(50^2+48^2+...+2^2\right)-\left(49^2+47^2+...+1^2\right)\)
Tính nhanh :
\(\left(1-\frac{1}{2^2}\right)\left(1-\frac{1}{3^2}\right)\left(1-\frac{1}{4^2}\right)...\left(1-\frac{1}{100^2}\right)\)
Giúp mình với !
Tính
\(A=\left(\frac{1}{2^2}-1\right).\left(\frac{1}{3^2}-1\right).\left(\frac{1}{4^2}-1\right)...\left(\frac{1}{98^2}-1\right).\left(\frac{1}{99^2}-1\right)\)
