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Zorluk: OrtaOrder of Operations and Number Properties

For all real numbers aa and bb, a custom operation ∗\ast is defined by a∗b=a2−2ba \ast b = a^2 - 2b. What is the value of the expression 2∗(3∗4)2 \ast (3 \ast 4)?

  1. 2Cevap
  2. B
    -4
  3. C
    8
  4. D
    -52
  5. E
    -3

Cevap

2
Evaluating the parentheses first gives 3∗4=32−2(4)=9−8=13 \ast 4 = 3^2 - 2(4) = 9 - 8 = 1. Substituting this back into the expression yields 2∗12 \ast 1. Evaluating this gives 22−2(1)=4−2=22^2 - 2(1) = 4 - 2 = 2, which is the correct value.

Adım Adım Çözüm

1
Evaluate the expression inside the parentheses: 3∗43 \ast 4.
3∗4=32−2(4)=9−8=13 \ast 4 = 3^2 - 2(4) = 9 - 8 = 1
According to the order of operations, expressions inside parentheses must be evaluated first.
2
Substitute the result back into the main expression.
2∗(3∗4)=2∗12 \ast (3 \ast 4) = 2 \ast 1
The evaluated value of the parentheses is substituted back to continue solving.
3
Evaluate 2∗12 \ast 1 using the operation definition.
2∗1=22−2(1)=4−2=22 \ast 1 = 2^2 - 2(1) = 4 - 2 = 2
Applying the definition of the custom operation to the remaining terms yields the final answer.

Anahtar Kavram

Order of Operations and Custom Arithmetic Operations
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