Let f (x)=x-2 and g(x)=x to the second power -7x-9.find f (g(-1))

Mathematics

1 answer:

Degger [83]2 years ago

5 0

f(g(-1)) = - 3

Evaluate g(-1) and substitute into f(x)

g(-1) = (-1)² -7(-1) - 9 = 1 + 7 - 9 = - 1

f(g(-1)) = (-1) - 2 = - 3

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Type the correct answer for each box write your answer in decimal form rounded to the nearest tenth if necessary type the soluti

stira [4]

The solution is $x=-1$ and $x=-0.5$

Step-by-step explanation:

The expression is $2x(x+1.5)=-1$

Multiplying the term $x+1.5$ by $2x$ , we get,

$2x^{2} +3x=-1$

Adding both sides by 1,

$2x^{2} +3x+1=0$

Taking factor, we get,

$\begin{array}{r}{x^{2}+2 x+x+1=0} \\{2 x(x+1)+1(x+1)=0} \\{(2 x+1)(x+1)=0}\end{array}$

Equating the factors to 0,

$\begin{aligned}2 x+1 &=0 \\2 x &=-1 \\x &=-\frac{1}{2}\\x&=-0.5\end{aligned}$ and $\begin{aligned}x+1 &=0 \\x &=-1\end{aligned}$

Thus, the smaller value is $x=-1$

The solution is $x=-1$ and $x=-0.5$

3 0

3 years ago

Please help with this

slava [35]

Answer:

D) x= $\frac{-2+-2\sqrt{7} }{3}$

Step-by-step explanation:

The quadratic formula is : $\frac{-b+-\sqrt{b^2-4ac} }{2a}$

A in terms of this question=9

B in terms of the question is 12

C in terms of the question is -24.

This question is an example of a quadratic equation. To work this out you may first need a calculator. The first step is to substitute the values of a,b and c into the formula. So once substituted the formula of $\frac{-b+-\sqrt{b^2-4ac} }{2a}$ becomes $\frac{(-12)+-\sqrt{(12)^2-4*(9)*(-24)} }{2(9)}$ . Although when written in a calculator there will not be a plus and minus button and so you would have to do this separately.