It is known that 1 plus 2 plus 3 plus. Plus 31 plus 32 plus 33 equals 17 times 33 to find 1 minus 3 plus 2 minus 6 plus 3 minus 9 plus 4 minus 12 plus. Plus 31 minus 93 plus 32 minus 96 plus 33 minus 99

It is known that 1 plus 2 plus 3 plus. Plus 31 plus 32 plus 33 equals 17 times 33 to find 1 minus 3 plus 2 minus 6 plus 3 minus 9 plus 4 minus 12 plus. Plus 31 minus 93 plus 32 minus 96 plus 33 minus 99

(1) From 1 + 2 + 3 +. + 32 + 33
=(1+33)×33÷2
=17×33.
=561
(2)(1-3)+(2-6)+(3-9)+(4-12)+.+(31-93)+(33-96)
=(1+2+3+.+33)-(3+6+9+12+.+96+99)
=(1+2+3+.+33)-3(1+2+3+.+32+33)
=(1+2+3+.+33)×(1-3)
=17×33×(-2)
-561×2
=-1122.