Sujit Prasad Kushwaha

This is the mathematics formulae book for class 12 students. Here, we have covered all the formulae needed to solve the questions of Mathematics. Permutation The total arrangement of total objects taken some or all at a time is called permutation. The permutation of 'n' objects taken 'r' at a time is denoted by $^np_{r}$ and is defined by; 1. $^np_{r}=\frac{n!}{(n-r)!}$ 2. Permutation of an object, all different;$$=\frac{n!}{p!\,q!\,r!}$$ where,  n=total objects p=repetition of first kind  q=repetition of second kind r=repetition of third kind 3. Circular permutation= $(n-1)!$ 4. If clockwise and anticlockwise arrangement are not distinguishable [necklace of beads and beads into bracelet]; Total number of permutation=$\frac{(n-1)!}{2}$ Combination The selection of total objects taken some or all at a time is called combination. The combination of 'n objects taken 'r' at a time is denoted by $^nc_{r} \, or \, c(n,r)$ and defined by; $$^nc_{r}=\frac{n!}{(n-r)!...

Prithvi Jayanti is a national holiday in Nepal that is celebrated on Poush 27 th every year to commemorate the birth anniversary of King Prithvi Narayan Shah, who is considered as the "Father of Nation" and the founder of modern Nepal. King Prithvi Narayan Shah is revered as one of the greatest kings in Nepal's history. King Prithvi Narayan Shah, who was born on January 11 th , 1723 (Poush 27 th 1779 B.S.), was the first ruler of Nepal who united the small kingdoms of Nepal into a single nation-state in 1769. He is credited with laying the foundations of a strong and centralized state in Nepal, and his vision and leadership played a crucial role in the country's development and progress. He also led Nepal in its successful resistance against attempts by the British East India Company to expand its influence in the region. On Prithvi Jayanti, Nepalis across the country pay homage to King Prithvi Narayan Shah and celebrate his legacy. The day is marked by patrioti...

 1. Read the following passage and answer the questions given below briefly: [10] There is a considerable scientific disagreement about the medical hazards of the new pollutants; about the effects of DDT now found in human bodies, about the diseases due to smog, or about the long range effects of fallout. But the crucial point is that the disagreements exists, for they reveal that we have risked these hazards before we know what harm they might do. Unwittingly we have loaded the air with substances that interfere with the functioning of the blood. Because we wanted to build nuclear bombs and kill mosquitoes; we have burdened our bodies with strontium-90 and DDT, with consequences that no one can now predict. We are, in effect, conducting a high experiment ourselves. A generation hence-too late to help-public health statistics may reveal what hazards are associated with these pollutants. ('Science and Survival,' Barry commoner) a) What are the three pollutants with which man has...

The Largest Structure in the Universe that you are referring to is known as the "Sloan Great Wall," and it is a vast supercluster of galaxies located in the constellation Pisces. The supercluster was discovered in 2003 by a team of astronomers using data from the Sloan Digital Sky Survey, and it is thought to be the largest known structure in the universe. The supercluster consists of 830 separate galaxies that are contained within four connected galaxy clusters. It stretches across an estimated distance of 1 billion light years and is thought to contain the mass of about 500 trillion suns. The Sloan Great Wall is so large that it takes light billions of years to traverse it, meaning that we are observing it as it was when the universe was much younger. The discovery of the Sloan Great Wall has provided important insights into the structure and evolution of the universe. Credits: NASA, ESA, Images by Science Photo Library

Father KN Waiba and mother Amrit Moktan gave a birth to a new child in Ligiya Tea Garden, Darjeeling, India in the year of BS 1994, Baishakh and they baptised the newly born child Bishnu Kumari Waiba. The child later chose ‘Parijat’ as her pen name when she ventured into the world of literature. She suffered from the diseases like tuberculosis, asthma, and rheumatism, a bright star of Nepali literature couldn’t continue her higher education after she completed graduation from Padma Kanya Campus, Kathmandu. Her first poem was published in the ‘Dharti’ magazine in 2013 BS. She is a poet, essayist, storyteller and novelist too. Her writing depicted the feelings of underprivileged and marginalised people. She is famous for her novels Siris Ko Phool, Mahattahin, Bainsh Ko Manche, Parkhal Bhitra Ra Bahir, Toribari Bata Ra Sapanaharu, and Antermukhi. Image source: Wikipedia