If I have this $(3 \times 4 + 2)^2$,
How can I simplify it with out the final result.
Do I distribute the $^2$ over each number like this:
$(3^2 \times 4^2 + 2^2)$?
What is the rule?
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If I have this $(3 \times 4 + 2)^2$, How can I simplify it with out the final result. Do I distribute the $^2$ over each number like this: $(3^2 \times 4^2 + 2^2)$? What is the rule? |
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$(3 \times 4 + 2)^2 = (12 + 2)^2 = 14^2 =196$ while $(3^2 \times 4^2 + 2^2) = 9 \times 16 +4 = 144+4 = 148$, so that does not work. If you want a rule for squares of sums, try: $$(x+y)^2 = x^2 + 2 x y +y^2.$$ |
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Always go basic by using the order of operations:
Using the PEMDAS rule, first simplify the parentheses, then simplify the exponent(s). We have,$$ 3 \times 4 + 2$$in the parentheses. Notice that again, PEMDAS is applied. Multiplication is done before addition. So, the simplification of the parentheses is as follows. $$\begin{align}3 \times 4 + 2 & = \color{maroon}{3 \times 4} + 2 \\ & = 12 + 2 \\ & = 14 \end{align}$$Now, the exponent. We'd have everything simplified as shown below: $$\begin{align} (3 \times 4 + 2)^2 & = & 14^2 \\ & = & 14 \times 14 \\ & = & 196 \end{align} $$ |
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No you can't distribute the powers like what you did. There is a theorem called the binomial theorem that controls this type of operations. The result is clearly $196$. Here is one way to get this result (steps are simplified so that you can follow) You can do this to simplify the expression: $$x=(3\cdot4+2)^2$$ then $$x=(12+2)(12+2)$$ $$x=(12\cdot12)+2\cdot(12\cdot2)+(2\cdot2)$$ $$x=144+48+4 = 196$$ An expression like: $$x=(a+b)^2$$ can be written as: $$x=(a+b)(a+b)=a\cdot a+2\cdot a\cdot b+a\cdot a = a^2+2ab+b^2$$ |
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No, you can't distribute the power on any operator, power is distributed on $\times$ and $\div$ not on $+$ and $-$ |
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Can you simplify $$(3\times4 + 2)?$$ then$$(3\times4 + 2)^2$$ by definition $a^2 = a\times a$ $$ = (3\times4 + 2)\times(3\times4 + 2)$$
multiplication before addition within the parentheses The distributive property of multiplication applies to coefficients not to exponents. a(b+c) = ab+ac If the 2 was in front as a coefficient then you could write: $2(3\times 4 +2)$ $= 2\times3\times 4 +2\times 2$ |
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