Math  /  Algebra

QuestionThe functions g g and t t are defined for xR x \in \mathbb{R} as follows: g:x4x5t:xx25x+1\begin{array}{l} g: x \rightarrow 4x - 5 \\ t: x \rightarrow x^2 - 5x + 1 \end{array} (a) Find t(6) t(6)
(b) Show that t(g(x))=16x260x+51 t(g(x)) = 16x^2 - 60x + 51

Studdy Solution

STEP 1

1. We are given two functions: g(x)=4x5 g(x) = 4x - 5 and t(x)=x25x+1 t(x) = x^2 - 5x + 1 .
2. We need to evaluate t(6) t(6) .
3. We need to show that t(g(x))=16x260x+51 t(g(x)) = 16x^2 - 60x + 51 .

STEP 2

1. Evaluate t(6) t(6) .
2. Substitute g(x) g(x) into t(x) t(x) to find t(g(x)) t(g(x)) .
3. Simplify the expression for t(g(x)) t(g(x)) .
4. Verify that the simplified expression matches 16x260x+51 16x^2 - 60x + 51 .

STEP 3

Substitute x=6 x = 6 into t(x) t(x) :
t(6)=625(6)+1 t(6) = 6^2 - 5(6) + 1

STEP 4

Simplify the expression:
t(6)=3630+1 t(6) = 36 - 30 + 1 t(6)=7 t(6) = 7

STEP 5

Substitute g(x)=4x5 g(x) = 4x - 5 into t(x) t(x) :
t(g(x))=((4x5)2)5(4x5)+1 t(g(x)) = ((4x - 5)^2) - 5(4x - 5) + 1

STEP 6

Expand (4x5)2 (4x - 5)^2 :
(4x5)2=(4x)22(4x)(5)+52 (4x - 5)^2 = (4x)^2 - 2(4x)(5) + 5^2 =16x240x+25 = 16x^2 - 40x + 25

STEP 7

Substitute the expanded form back into the expression for t(g(x)) t(g(x)) :
t(g(x))=(16x240x+25)5(4x5)+1 t(g(x)) = (16x^2 - 40x + 25) - 5(4x - 5) + 1

STEP 8

Simplify the expression:
t(g(x))=16x240x+25(20x25)+1 t(g(x)) = 16x^2 - 40x + 25 - (20x - 25) + 1

STEP 9

Combine like terms:
t(g(x))=16x240x+2520x+25+1 t(g(x)) = 16x^2 - 40x + 25 - 20x + 25 + 1 t(g(x))=16x260x+51 t(g(x)) = 16x^2 - 60x + 51

STEP 10

Verify that the expression matches 16x260x+51 16x^2 - 60x + 51 .
The expression matches, confirming the result.
The value of t(6) t(6) is 7 \boxed{7} , and it is shown that t(g(x))=16x260x+51 t(g(x)) = 16x^2 - 60x + 51 .

Was this helpful?

Studdy solves anything!

banner

Start learning now

Download Studdy AI Tutor now. Learn with ease and get all help you need to be successful at school.

ParentsInfluencer programContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord