Enable contrast version

# Tutor profile: John T.

Inactive
John T.
Tutor for 5 years
Tutor Satisfaction Guarantee

## Questions

### Subject:Trigonometry

TutorMe
Question:

If a=5, b=8 and c=10 Find $$\cos A$$

Inactive
John T.

Using the law of cosines, we have $$\cos A=\frac{b^2+c^2-a^2}{2bc}$$ Plug in the values $$\cos A=\frac{8^2+10^2-5^2}{2\times8\times10}=\frac{139}{160}=0.8688$$ Hence, $$\cos A=0.8688$$

### Subject:Calculus

TutorMe
Question:

Find the equation of the normal to the curve $$y=2x^2-3x+5$$ at the point (5,8)

Inactive
John T.

Answer: We know that the slope of the tangent at any point (x,y) is given as $$m=y'$$ We will find the slope of tangent at (5,8) Here $$y'=4x-3$$ So the slope of tangent at (5,8) is $$m=4\times5-3=20-3=17$$ But the slope of normal is $$m_n=-\frac{1}{m}=-\frac{1}{17}$$ And using the point slope form, we have equation of normal as $$y-k=m_n(x-h)$$ where (h,k) is the point. Here h=5 and k=8 for the point (5,8) So the equation of normal is $$y-8=-\frac{1}{17}(x-5)$$ Simplify $$y=-\frac{1}{17}x+\frac{141}{17}$$ Hence, the required equation of the normal is $$y=-\frac{1}{17}x+\frac{141}{17}$$

### Subject:Algebra

TutorMe
Question:

What would be the remainder when $$f(x)=3x^3-2x^2+5x-2$$ is divided by $$(x-3)$$

Inactive
John T.

Remainder theorem states that when a polynomial f(x) is divided by $$(x-a)$$, the remainder is equal to $$f(a)$$. According to the remainder theorem, Remainder$$=f(3)=3\times3^3-2\times3^2+5\times3-2\\=81-18+15-2\\=76$$ Hence, the remainder is 76

## Contact tutor

Send a message explaining your
needs and JOHN will reply soon.
Contact JOHN

Start Lesson

## FAQs

What is a lesson?
A lesson is virtual lesson space on our platform where you and a tutor can communicate. You'll have the option to communicate using video/audio as well as text chat. You can also upload documents, edit papers in real time and use our cutting-edge virtual whiteboard.
How do I begin a lesson?
If the tutor is currently online, you can click the "Start Lesson" button above. If they are offline, you can always send them a message to schedule a lesson.
Who are TutorMe tutors?
Many of our tutors are current college students or recent graduates of top-tier universities like MIT, Harvard and USC. TutorMe has thousands of top-quality tutors available to work with you.
BEST IN CLASS SINCE 2015
TutorMe homepage