Question

Find the value of the expression when x = -1 a) 3x³ +2x -1
b) 2x²- x+ 6​

Answer 1

a is -6 and b is -9 as -1 cube -1

Answer 2

✯Given✯

➥ 3x³ +2x -1

➥ For x = -1

➥ 3(-1)³+2(-1)-1

➥ 3(-1)+(-2)-1

➥ -3-2-1

➥ -6

☆ Value of expression 3x³ +2x -1 where x is - 1 is -6

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➦ 2x²- x+ 6​

➦ For x = -1  

➦ 2(-1)²-(-1)+6

➦ 2(1)+1+6

➦ 2+1+6

➦ 9

☆ Value of expression 2x²- x+ 6​ where x is - 1 is +9

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