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Factor out a 2^20, and you have 1023 left in the parenthesis. Notice that 2^20 =(2^10)^2=1024^2. So you end with 1024(1024)(1023). Just do some standard multiplication by hand and you’re done.
I'd rather use the calculator. The error rate with manual calculations is far too high and is no fun!
I gotta say, subtracting the square of 1024 from the cube of 1024 seems easier.
1^3 ➖ 1^2 3 ➖ 2 (x ➖ 3x+2).
2^30-2^20=(2^10)^2•(2^10-1)=1024^2•(1024-1). set a=24=(1000+a)^2•(1000+a-1)=(10^6+2000a+a^2)(1000+a-1)=10^9+a•10^6-10^6+2a•10^6+2a^2•10^3-2a•10^3+a^2•10^3+a^3-a^2=10^9+(3a-1)10^6+(3a^2-2a)10^3+a^3-a^23a-1=3*24-1=71 a(3a-2)=24*70=1,680 a^3-a^2=24^2*23=13,248 1000+71=1,071 1,071,000+1,680=1,072,680 1,072,680,000+13,248=1,072,693,248
10
One TB - one GB.
dumb exercise leave it
Quatsch.
Factor out a 2^20, and you have 1023 left in the parenthesis. Notice that 2^20 =(2^10)^2=1024^2. So you end with 1024(1024)(1023). Just do some standard multiplication by hand and you’re done.
I'd rather use the calculator. The error rate with manual calculations is far too high and is no fun!
I gotta say, subtracting the square of 1024 from the cube of 1024 seems easier.
1^3 ➖ 1^2 3 ➖ 2 (x ➖ 3x+2).
2^30-2^20=(2^10)^2•(2^10-1)
=1024^2•(1024-1). set a=24
=(1000+a)^2•(1000+a-1)
=(10^6+2000a+a^2)(1000+a-1)
=10^9+a•10^6-10^6+2a•10^6
+2a^2•10^3-2a•10^3+a^2•10^3
+a^3-a^2=10^9+(3a-1)10^6
+(3a^2-2a)10^3+a^3-a^2
3a-1=3*24-1=71
a(3a-2)=24*70=1,680
a^3-a^2=24^2*23=13,248
1000+71=1,071
1,071,000+1,680=1,072,680
1,072,680,000+13,248=1,072,693,248
10
One TB - one GB.
dumb exercise leave it
Quatsch.